CONTENTS:

Partes I et II.

Published May 25, 1897.

I e tre stl RR te se à à» à K. Mitsukuri. ig

Pear-boror (Nephopteryx rubrizonella, Kag.) With

ÉCRIRE ace n AI eee te esse eee els IUISUMAN A... 1.

On Two New Species of Asthenosoma. With Plate II.....S. Yoshiwara...... 5.

Chaetognaths of Misaki Harbor. With Plate IIL.......... Tre Ata ates 1. 13.

On the Accommodation of Some Infusoria to the Solution

of Certain Substances in Various Concentrations....... AIR as aerei (23%

On Changes which are found with Advancing Age in the

Calcareous Deposits of Stichopus japonicus, Selenka..K. Mitsukuri...... 31.

Revision of Hexactinellids with Discoctasters, with De-

scriptions of Five New Species..….....…...........,......…. I Tunzeos nen... 43.

Mis cellaMme GUS. NobES nee. « ee RER iena 61.

Ueber eine in Misaki vorkommende Art von Ephelota und iiber ihre Sporen-

bildung, vou ©. Isarxawa.—-Die Entwickelung der Gonophoren bei Physalia

maxima, von S. Goro.—On the Fate of the Blastopore, the Relations of the

Primitive Streak, and the Formation of the Posterior End of the Embryo

in Chelonia, together with Remarks on the Nature of Meroblastie Ova in

Vertebrates, by K. Mrrsuxurt.—Living Specimen of Pleurotomaria Bey-

richii.— The Ophiuran Shoal.—Zoological Society of Tokyo.—List of

Japanese Zoologists.

Pars III.

Published August 10, 1897.

On a Mode of the Passage of the Eye in a Flatfish......... T. Nishikawa..... 78.

On the Growth of the Ovum in Chaetognaths. With

LA FRA Re SRO I SARAI RR AUTRE Te 77

Notes on the Paludina-Species of Japan. With Plate V...T. Iwakawa....... 83.

Dendrocoryne, Inaba, Vertreterinn einer neuen Familie

dee Hydromedusen.: Mit Taf. VI... Sh GANN 93.

On a New Species of Malacobdella (M. Japonica). With

LUE OR ee AAA tt! A eres nce PER U. Takakura...... 105.

Notes on the Breeding Habit and Development of Rhaco-

phorus Behlegelii, Günther... An... essen Se 113.

ME ee RN I ninni 123.

Zoological Society of Tokyo. —The Nee Imperial University of Kyoto.

Pars IV.

Published November 5, 1897.

Note on an Amphioxus obtained in Amakusa, Kyushyu...H. Nakagawa..... 125.

On a New Species of Elasipoda from Misaki.................. K. Mitsukuri...... 188.

Preliminary Note on the Development of the Pronephros

in PetromyZON 2-28... BOARA stor: 137.

Sur une nouvelle espèce japonaise du genre Lucernaria...A. Okd.......+.... 141.

Sur une nouvelle espèce japonaise du genre Phoronis........ A SONATE a 147.

Miscellaneous Notes... cesse TO 149.

The Occurrence of Sphærothuria bitentaculata, Ludwig in the Sagami Seas.—

Contributions to the Morphology of Cyclostomata. I. On the Formation of

the Heart in Petromyzon, by S. Harra.—Zoological Society of Tokyo.

Personal News... ocean. E eee eee TI asile

List of Publications received in exchange for the Anno-

tationes uutil October, 1897, arranged alphabetically

according to AUtOISTOFISOCIEHMES AN E I I emer 152.

List of Names to which the Annotationes are regularly

SEHE suini rca zato nen nee anne en. en een ee EEE 152.

List of Publications received by the Zoological Society

of Tokyo before the issue of the Annotations.............. sese erre sirene» 159.

Erratum.

In Mr. Ikeda’s paper beginning at page 113 read Rhacophorus instead of Raco-

phorus.

HAAS 4 2 4 %

di — 45 3 — KE _MW

We StH A THA ER

UL 17 1897

ANNOPATIONES

ZOOLOGICÆ JAPON ENSES

AUSPICIIS

SOCIETATIS ZOOLOGICÆ TOKYONENSIS

SERIATIM EDITA.

Volumen I. Partes I et II.

TOKYO:

PUBLISHED May 25, 1897.

NOTICE.

The “ Annotationes Zoologicæ Japonenses ” are published quarterly,

in January, April, July, and October.

Terms of subscription—$1®=4s=F5= M4 per annum; single parts

25&=1s=F1.25=MI1 each. Postage included in all cases.

Remittances from foreign countries are to be made by postal money

orders, payable in Tokyo to M. Namiye, Zoological Institute, Imp. Univ.,

Tokyo.

TO CONTRIBUTORS.

Articles may be written in English, German, French, or Italian.

Each contributor receives 50 copies of the reprints of his article

gratis. Any number of extra copies will be furnished at cost.

Contributors are particularly requested to specify the number of

reprints they want at the end of the manuscript. If not specified 50

copies will be delivered.

Articles may be accompanied by simple illustrations, as far as pos-

sible in lines and dots.

Communications are to be addressed to the Secretary of the Zoologic-

al Society of Tokyo, Zoological Institute, Imp. Univ., Tokyo.

INTRODUCTORY.

The duty of introducing the present modest publication to our

fellow workers of other lands, and of explaining its aim and scope,

having fallen on me, I feel that I can do this in no better way than

by offering a brief retrospect of the progress of our science in

Japan.

Until within a comparatively recent time, Japan was a sealed

book to Europe. The name of our country stood in the West as

the symbol of things strange, remote and antipodal. In the minds

of Europeans, Japan has never been associated with science, except

as an object of investigation ; and, if I mistake not, they would find

something almost incongruous in the idea of contributions to the

progress of modern science from Japanese sources. But if such a con-

ception exists, it rests, I verily believe, on entirely unjust grounds.

A slight acquaintance with the history of Japan would enable any

one to see without much difficulty that a high degree of culture was

attained at an early age in our land, and that there has ever been

abroad a spirit of earnest study among our people. It would take

me too far away from my immediate object to do any thing more

than mention the existence of those masterpieces in literature and

art which were produced in the period extending from the sey nth to

ii INTRODUCTORY.

the tenth centuries of the Christian era and which have been the

despair of all who have striven to emulate them in succeeding ages.

But I may perhaps be allowed to cite a few facts having a closer

connection with our subject, which would, I believe, go far to sub-

stantiate what I have claimed for my country.

It is probably unknown to most persons in the West that early

in the eighth century of the Christian era there was already estab-

lished in Japan an Imperial University with four departments,—

Ethics, History, Jurisprudence and Mathematics,—and with the pre-

scribed number of four hundred students. There were also at the

same time a bureau devoted to Astronomy, Astrology, Calendar-Com-

pilation and Meteorology, and a Medical College with professors of

Medicine, Surgery, Acupuncture, Necromancy (the art of healing by

charms) and Pharmacology. The last named branch of study in-

cluded the collection, cultivation, and investigation of medicinal plants,

and thus a considerable amount of botanical knowledge must already

have been acquired by that time. ‘Toward the end of the ninth

century, when a catalogue of books existing in Japan was compiled

by the order of the then reigning Emperor, the Imperial library

was found to contain 16,790 volumes, divided into forty depart-

ments,—and this in spite of a disastrous fire of some years previous.

Among the medical works were some with very moderu sounding

titles, such as “ The Curing of Diseases of Women” and “On the

Methods of Healing Diseases of the Horse.” Japan in those early

days derived its culture from India, China, and Corea, but the details

above enumerated clearly show that educated society must already

have attained a high degree of civilization.

Coming to more, modern times, it is known that, during the

INTRODUCTORY. lil

long peace of two hundred and fifty years which the rule of the

T'oxuGawa shoguns secured for Japan, literature, the arts, and all

peaceful industries were developed with remarkable vigor and

rapidity, and that the study of Natural History shared in this pro-

gress. Apart from that innate love of Nature and the natural which

was ever showing itself in poetry and other arts, the study of

natural products was always pursued, ostensibly with the purpose

of collecting materia medicu, or of discovering things that might

be used as food in case of a famine, or of identifying objects

mentioned in the Confucian classic, “ Shi-King.” But it is not

difficult to perceive that naturalists looked in reality beyond these

simple or utilitarian ends, and investigated animals and plants

for their own sake, although the principal aim of their researches

seems to have been the comparatively barren one of establishing

a relationship between Japanese products and those described in

various Chinese works on Natural History. Frequent were the

excursions and expeditions undertaken with the view of collecting

natural objects, among which plants were especial favorites, and

all parts of the country seem to have been tolerably well explored

in this way. Numerous were the treatises on Natural History,

published or unpublished. Many of. these were encyclopedic in

their comprehensiveness and size, such as “ Shobutsu Ruisan,” by

Inao Jakusut, (1000 parts, early in the eighteenth century), and

‘“Honzò Komoku Keimo” by Ono RANZAN (48 parts, 1803). The

last named naturalist was so famous for his extensive knowledge that

we are told, his pupils were nearly one thousand in number. My

colleague, Prof. Marsumura, in his book on the enumeration of

Japanese plant-names, gives 306 titles of Japanese works on botany

1V INTRODUCTORY.

compiled previously to 1868. Many of the Natural History

volumes had beautiful colored illustrations, which serve their pur-

pose even at the present day. Natural History displays were of

common occurrence, when naturalists came together with their

treasures, and showed them to one another and to the public.

Of these the exhibitions given by HiraGa GENNAI in the middle

of the eighteenth century were perhaps the most celebrated. The

present Botanic Garden of the Imperial University was established

early in the TokUGAWA period, viz. in 1681, and was long renown-

ed as the “O Yaku En” (Garden of Medicinal Plants). The

mastery of the Dutch language by a few earnest physicians in

the middle of the eighteenth century has always seemed to me

one of the greatest triumphs ever achieved by patient scholarship.

Originally undertaken with the purpose of ascertaining something

about Western medicine, their efforts soon exerted an influence on

all branches of learning. The whole rich treasury of Western

civilization became suddenly accessible through the channel thus

opened of the Dutch language. It is not possible to overestimate

the effect of the new acquisition on the progress of Japan. Suffice

it here to say that the country would not be what it is to-day,

but for this leaven which had been working through and through

the whole mass of society for over a hundred years before the

Restoration of 1868 enabled it to bear its legitimate fruit. This

innovation, ‘together with the visits of THUNBERG (1775) and

SIEBOLD (1821), had due effect upon the Natural History studies

also. The system of Linné, especially in regard to plants, seems

to have been well grasped, with very little delay. The most famous

productions of the new school on Natural History subjects are pro-

INTRODUCTORY. V

bably “ Shokugaku Keigen” (Elements of Botanical Science) by

UpAGawAa Yoan, 1835; and “ Somoku Zusetsu” (Icones Plantarum)

by Imuma Yokusar, 1832 ;—the latter being a standard work at

the present day. It is perhaps a circumstance interesting enough

to record, that a work on the use of the microscope was published

in 1801.

Looked at from the modern standpoint, the Natural History of

the pre-Restoration period (before 1868) was without doubt strongest

in Botany. Our science of Zoology seems to have been greatly

backward in its development, compared with that of the sister

science. and its study was probably similar in method and aim to

that of the Middle Ages in Europe. It seems to have concerned

itself mostly with making commentaries on Chinese works of

Natural History, like “ Honzo Komoku” or with identifying Japanese

objects with names given in those writings. Excepting a little

on birds, fishes and shells, hardly any work that can be called

scientific in any modern sense, seems to have been accomplished.

Nevertheless this school did an immense service by showing that

the study of natural objects was worth the best efforts of intellectual

men. Names like Akar HAKUSEKI, INAo JAKUSUI, KAIBARA EKKEN,

Ono RANZAN* are among the most honored in the annals of our

learning.

With the Restoration of the Emperor to his full power, in

1868, came the wholesale reconstruction of all political institutions,

and the country has been, and is still, going through such a

social revolution as has seldom been witnessed in any part of the

world. Along with many other things, the old school of Natural

* All these names are given in the Japanese fashion, with the surname first.

VI INTRODUCTORY.

History was swept away, as chessmen from the board at the end

of a game. So far as our science is concerned, there is a complete

break at this period. ‘The modern school of Zoology dates from

the appointment of Prof. E. S. Morse of Salem, Mass., U. S. A.

to the chair of Zoology at the University of Tokyo, in 1877.

His indefatigable zeal and genial manners won many friends for

the new science among all classes of society, while his lectures,

popular or otherwise, drew attention for the first time to the im-

mense strides which our science, under the stimulus of Darwinism,

was making in the West. He, with a few students under him,

also soon had in working order a tolerably good museum—the

nucleus of the present Zoological and Anthropological collections sof

the Science College. It was also during his stay and through

his care that the Tokyo Biological Society, from which the

Tokyo Zoological Society is directly descended, was first organized.

It is truly wonderful how much he accomplished in the brief

time he was in Japan. On the return of Prof. Morse to America,

he was succeeded by Prof. C. ©. WHITMAN, now of the University

of Chicago. It was the latter who first introduced modern

technical methods. These two Americans, MORSE and WHITMAN,

thus stood sponsors to the modern school of Zoology in Japan.

Since 1881, the development of Zoology in this country has

been entirely in the hands of Japanese.* The spirit of earnest

* Some who read this statement may consider that I have not given due credit to

those zoologists from other countries who have lived in, or visited, Japan from time to

time. It is certainly as far as possible from my iutention to slight the labors of

HILGENDORF, DÖDERLEIN, PRYER and others, but the fact remains that the recent

development of the zoological school in Japan has been almost entirely independent of

these men. It is a pleasure to me to add that Mr. Owsron of Yokohama has been

very active in unearthing the treasures of the deeper parts in the Sagami Sea. E

INTRODUCTORY. vil

study which signalized the Natural History School of the pre-

Restoration days is happily revived, but with higher and wider

purposes, and with greater facilities for successful attainment.

Though only twenty years have passed since the “new departure,”

a vigorous school of Zoology has already sprung up. I shall

perhaps not be overstepping the bounds of modesty, if I say for

my confreres that a more earnest, more enthusiastic, or more

industrious set of men could with difficulty be found anywhere.

There can be no doubt that the establishment of the Marine

Station at Misaki, by the Imperial University, in 1887, gave a

great impetus to the study of Zoology in Japan. Situated at the

point of the peninsula jutting out between the Bay of Sagami

and the Bay of Tokyo, it has access to localities long since famous

as the home of some remarkable forms of animal life. Along the

coast, all sorts of bottoms are found, yielding a rich variety of

animal forms, while the hundred-fathom line is within two or

three miles of the shore, and depths of five hundred fathoms are

not very difficult of approach. The existence of a remarkable

deep-sea fauna in these profounder parts has been ascertained

within the last few years, and zoological treasures are now being

constantly hauled up. The great “ Black Current” (Kuro Shiwo)

sweeps by, not many miles out, and a branch of it often comes

into the very harbor of Misaki, gladdening the heart of the Plankton

explorer. Face to face with this inexhaustible treasury of animal

forms, the zoologist will have to possess unusual powers of self-

restraint, indeed, not to grow enthusiastic over his science.

by the year 1888, the number of those devoted to the study

of Zoology in our country had so fax increased that the need of an

vili INTRODUGTORY.

organ of their own was felt. Thus was established in that year,

under the auspices of the Tokyo Zoological Society, a monthly

publication entitled the “ Döobutsugaku Zasshi” (Zoological Maga-

zine). This had a twofold design; first, to serve as a means of

communication among followers of the science in Japan, and secondly

to spread the knowledge of Zoology among non-specialists, especially

among teachers of the subject in primary and middle schools.

The periodical is in the Japanese language, and popular as well as

special papers have been published side by side. The Magazine

is now in its ninth volume.

About the same time, the Journal of the College of Science,

Imperial University, was established. Thus was opened a con-

venient channel for carrying abroad the intelligence of scientific

investigations conducted in Japan, and those who look over the

ten volumes of the Journal will see that zoologists have not been

slow in availing themselves of the opportunities afforded.

The prospects of our science in Japan have never been

brighter than they are at this time. All of its main branches,

including applications of it to practical purposes such as Fisheries,

Sericulture, Entomology, ete. are now fairly represented. Hach

year will see gradual additions to the specialists of different groups,

as the number of graduates from the Imperial University in-

creases. The Marine Station at Misaki, which has become

too small for our growing body, will be removed within the

present year to a new site, about two miles north of its present

location, and its accommodations will be considerably enlarged.

While perhaps not essential to the pursuit of science, the extreme

beauty of the situation, which commands a matchless view of

INTRODUCTORY. 1X

Fujiyama and the Sagami Bay, will certainly not lessen its attrac-

tions; and an additional charm to those who are interested in the

heroic achievements of the past may be found in the associations

with which the spot abounds, as the ancient stronghold of a

mighty warrior chieftain who was killed here in a desperate battle,

after sustaining a long siege, and whose spirit is believed by the

populace still to haunt the scene of his former greatness. A

proposed railway, passing near the new site, will bring the station

within two or three hours of Tokyo. A number of teachers

scattered over different parts of the country are acting somewhat

as sentinels at the outposts of our science, and doing good service

in collecting animals from different localities. Our field of activity

has also lately been suddenly widened by the addition of Formosa

to the territory of Japan, and the work of a collecter now on

that island will, it is hoped, be but the forerunner of many similar

undertakings. Hardly a week now passes without something new

turning up in the line of our study, and that something is often

of great interest.

Under these circumstances, it has seemed to us very desirable

that there should be opened some channel for communicating the

progress of our science in Japan to fellow-workers in other coun-

tries ;—some channel less formal than the Journal of the Science

College, and one through which even little things may be made

known. A beginning was made in this direction about two years

ago, when a department written in Huropean languages was added

to the Zoological Magazine, which has perhaps become known,

through this feature, to some who read these lines. We now

feel justified in taking another step forward. Arrangements are

x INTRODUCTORY.

now completed for publishing the part written in European

languages in an issue entirely separate from the purely Japanese

text of the Magazine. The latter will now go on, containing

sunply articles in our own language, and will be intended for

internal circulation, with its original twofold object. The present

publication will take the place of the foreign language part, and

will be primarily for the purpose of making the progress of Zoology

in Japan known abroad. It will be distributed among laboratories,

museums, educational institutions, and various societies of different

countries, much more extensively than was attempted with the

Zoological Magazine. We regret that the limited funds at our

command do not allow us to publish at as much length, or to make

use of as good plates, as we desire, but it is hoped that in time

there will be a marked improvement. For the present, the

ANNOTATIONES will be issued quarterly, four numbers constituting

an annual volume.

In future, therefore, zoologists of other countries may look

for contributions to their science from Japanese sources in two

publications :—for more extensive or monographic works in the

Journal of the College of Science, Imperial University, and for

shorter, less formal or preliminary notices in the present periodical.*

On behalf of my fellow-zoologists of Japan, I should like to

make here an earnest appeal to societies, institutions and indivi-

duals, the world over, to help us in our efforts, by sending their

publications to us. We who are so far from the centers of our

- * There are some other publications in which papers on zoological subjects are

published from time to time, for instance, Bulletin of the College of Agriculture,

Imp. Univ. It is our intention to call attention to them in this journal, when-

ever occasion arises. a i

INTRODUCTORY. xl

science in Europe and America appreciate this favor more keenly,

I think, than those situated more favorably have any idea of.

Publications may be sent either to the Tokyo Zoological Society

or to the College of Science.

We now send forth this magazine to our fellow-workers in

other lands, asking their lenient judgment for whatever short-

comings it may exhibit, and hoping that it will aid in promoting

that fraternal feeling which must ever be characteristic of inter-

national Science.

SALVE!

K. MirsugURI, Ph. D.

Professor of Zoology, Imperial University,

and President of the Tokyo Zoological

Society for 1896-7.

Pear-borer

(Nephopteryx rubrizonella, Rac.).

By M. Matsumura.

Agricultural College, Sapporo, Hokkaido.

With PI. I.

There are two species of our pear-borers belonging to the genus

Nephopteryx, the present one being much larger than the other. In

1889, the smaller species was described by Mr. S. IkEDA of the Ag-

ricultural College of Tokyo, in the Zoological Magazine, Vol. 1, page 99 ;

but its life history was not known clearly at that time. By this larger

borer our pear growers have been losing every year 30-50% of their

crops, it being a much more troublesome insect than the apple-borer

I have described in a recent number of the Zoological Magazine.

Entomologically it belongs to Microlepidoptera, group Pyradina, family

Phycidæ, and its generic and specific name was kindly identified for

me by Mr W. J. HoLLanp of Pittsburg, through the kindness of Mr.

O. Howarp, the first Entomologist in the Department of Agriculture,

U.S. A.

Imago--Antenn® curved over the basal joint, the latter with a

scaly tuft; labial palpi compressed, with a long end joint; maxillary

palpi small and filiform ; anterior wing with 11 veins, branches 4th. and

5th. not being stalked; ground color varying form grayish brown to

grayish black, crossed by two equidistant irregularly sinuated, grayish

bordered black lines. Outer margin and basal half much deeper in color,

with a black disco-cellular marking in the middle of the wing. Hind

wing dark gray, with 8 veins, branches 3rd., 4th., and 5th. springing

from a common stalk which rises from a hind angle of the closed

mid-cell.

2 M. MATSUMURA.

Thorax is of the same color as the anterior wing, abdomen much

paler ; hind tibia large and compressed, with 4 spines. Wing expanse 25

mm., body length 12 mm.; two broods in a year, first middle July,

second late September to early October.

Eggs—These are placed just under a small twig where the rain

does not strike directly, protected safely by a white silken web. The

eggs under that cover are about 20 in number; oblong in shape, both

ends being a little narrower ; very flat ; black in color; 0,7 mm.x0,4

mm. in size and hybernating through the winter in this state.

Larva—The larva hatch in early june, just at the time when the

pear attains the size of a cherry, at first spinning much silken thread on

the branches and then making their way to different fruits near by. To

the injured fruits are attached almost always silken threads just at the

place of branch, where a fruit stalk hung. At first whitish in color,

with black head and black first segment, the larve gradually change in

color to grayish yellow; and when fully mature, they take a pinkish

brown color, measuring about 20 mm. in length. They are

spindle shaped in general, consisting of 12 segments, of which the

Gth., 7th., and 8th. are the largest; head brownish black; the

upper part of the second segment with 2 pitchy black horny spots ;

legs show nothing unusual. They injure only the core of pears and

as they leave always a large blackish opening at their entrance, it

is easy to detect their presence. The larval stage lasts 3 weeks or

more; the insects I cultured have made cocoons on the 30th. of

June. Food plant only pear.

Pupa—It always changes to pupa within the core of the fruit

spinning very little silk ; it is deep red brown in color, head, thorax and

wing portion being much more so; it measures 13 mm.—15 mm.

in length ; pupal stage lasts more than 2 weeks.

Preventive method—The most effectual preventive method is to

take off the eggs during winter months, as they are easily recognizable

by their whitish web cover at the branches. For this purpose pruning

is indispensable, eggs being almost always on the top of the branches e

PEAR-BORER. 3

and when pruned they must be immediately burnt up; the remaining

branches must be carefully searched for. The eggs are always placed

near the hybernating nest of the pear leaf roller Rhodophea hollandella,

Rag. Kerosene emulsion is very beneficial after pruning as well as in

early June, namely the time of larve hatching, for it kills at the same

time the larve of the leafroller. After they bore into the fruit, no

remedy is accessible, except carbon bisulphide, but this chemical being

very expensive I only used it on a dwarf tree, pouring it with a small

brush into the hole, through which insect entered; it very soon kills

the insect and no injury was done to the fruit. Benzole also has the

same effect, but inferior, and little injures the fruits. Now in our

College garden, picking of the injured fruits by hands is the only means

resorted to, as they are easily recognizable by their black holes and

brown excrements. Lamp is of no use.

Entomological Laboratory,

Agricultural College, Sapporo.

Jan. 5th. 1897.

Printed April 30. 1897.

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Fig. 1; Imago enlarged.

Eis i); larva.

Fig. III, A; Eggs under the Silky Cover.

Fig. IV; Pupa in the Pear.

On Two New Species of Asthenosoma

from the Sea of Sagami.

By S. Yoshiwara.

Zoological Institute, Science College, Imp. Univ., Tokyo.

With Pl. Il.

The Echinoid collection of the Science College Museum contains,

amongst others, five interesting specimens referable to the genus As-

thenosoma, of which I propose to make two new species as described

below.

Asthenosoma longispinum, nov. sp.

(Figs. 1-7.)

Four specimens of this species have been obtained from a depth of

313-376 fathoms in Sagami Sea.

Test flexible, disc-shaped, flat actinally, depressed abactinally,

somewhat polygonal in ambital outline. Dimensions of the largest

specimens : 135 mm. in diameter and 18 mm. in height. Color of

covering membrane dark red as preserved in alcohol.

Plates numerous. In a specimen of 110 mm. in diameter, there

are in a vertical row : actinally, about 17 interambulacral and about 23

ambulacral plates ; abactinally, about 30 interambulacral and more than

80 ambulacral plates. Plates overlapping as in other species of the

genus. Between every two interambulacrals in vertical succession, there

exists actinally a considerable membranous area in the middle, but

abactinally this membrane is reduced to a minimum, and the plates

overlap one another even in the middle of transverse sutures, although

6 S. YOSHIWARA.

in a very slight degree. Close to the periproct again, the overlapping

Just referred to is not recognizable.

Apical system (fig. 5) star-shaped, not projecting, the plates lying

partly in apposition, partly separated by more or less wide membranous

interspaces. The larger and peripherally situated apical plates with

tubercles for pedicellariæ and secondary spines. Basals (bas.) wedged

into interambulacram and bearing a short membranous tube with

genital opening (g. 0.). Radials (rad.) separated from basals, usually

with a periproctal (per.) between. Anals (an.) very small, elongated,

closely packed together. Anus somewhat projecting.

Ambulacrum straight, narrower than interambulacrum (the ratio of

breadths of the two being 28 to 41 at ambitus),

Ambulacral plate is composed, as determined near ambitus, of an

aboral section and of a small, narrow, imperfectly calcified, adoral section

situated at the middle of lower edge (fig. 6, am.). Closer ‘observation

shows that the former again consists of three pieces apposed together in

a transverse row. A pair of pores is situated on the outermost piece of

the aboral,section. This pair of pores, together with two more pairs

found side by side on the adoral section, forms a tolerably broad pori-

ferous zone.—Towards the periproct the divisional lines between the

pieces making up the aboral section become more and more difficult to

distinguish and towards the periproct the adoral section apparently loses

one of its pairs of pores, so that there now remain only two pairs of

pores to each ambulacral (fig. 5, am... Finally the adoral section

itself is no longer recognizable as such and henceforth the row is-

continued to the periproct by a few, very imperfectly calcified plates,

each with a single pair of pores. |

Peristomal ambulacrum consists of transverselv narrow plates, each

with a single pair of pores. They are arranged in each peristomal ambu-

lacrum in two regular rows reaching the mouth, between which are

irregularly interposed a few other plates eonfined to the peristomal

periphery. The pairs of pores on the two rows form a continuation of

the outermost series of those of the coronal ambulacrum. ‘Those of

ON TWO NEW SPECIES OF ASTHENOSOMA. 7

interposed peristomal ambulacral plates form one or two irregular

series.

Tentacles of abactinal side, as also those situated near or within the

peristome, are smaller, more pointed and poorer in calcareous networks,

than the remainder of those of actinal side. They are also destitute of

calcareous discs present in the latter. Calcareous networks of tentacles

show special concentration along two symmetrically situated lines on

either side.

For the distribution and arrangement of large and small tubercles

on both ambulacrum and interambulacrum, the reader is referred to figs.

3 and 4.

Ambulacral arch of the perignathic girdle encloses a somewhat

triangular space. The circumferential surface of the arch shows

roughness at top for insertion of retractor muscles. On the other

surface there is roughness along its inner edge for insertion of the

muscle characteristic of the genus. Interambulacral ridge of the girdle

possesses two slight prominences. Close observation shows at once

that here the ridge is formed of one or two interambulacral plates derived

from each of the two rows that compose an interambulacrum, and that

each limb of the arch is formed by modification of a single ambulacral

plate—a condition that reminds us of what occurs in the Cidaride.

The sutures between all the plates composing the perignathic girdle

remain distinct.

Spines perforated, of four kinds: 1) long poison-spines, which are

smooth, cylindrical, tapering, of reddish color; some as long as 60

mm. or more; found scattered all over abactinal side; 2) stout hoof-

capped spines (fig. 7) similar to those generally found in Phormosoma

with shaft crenulated in upper part, found on abactinal side from a

short distance within ambitus and extending to peristomal margin ;

3) small slender spines like poison-spines but more or less crenulated

and covered with thicker membrane containing red pigment, occurring

intermixed with the two foregoing kinds; 4) those found thickly

crowded in proximity of peristome, densely crenulated and slightly

8 S. YOSHIWARA.

curved, with the concavity facing the peristome.

Pedicellariz of two kinds: small slender-stemmed trifid ones and

larger but short-stemmed cup-bearing ones. Both distributed all over

coronal, periproctal, and peristomal plates.

Spheeridia large, 1 mm. in length, arranged in a single series

closely inside the innermost series of tentacles, not only on actinal side

but also on abactinal side up to one-fourth of the way from ambitus to

periproct. Their membranous covering contains red pigment ; the club-

shaped calcareous body has numerous canals longitudinally traversing

the neck. These open mostly on the surface of neck, while only three

of them pass into the head to open there.

Branchia with branches that are either simple and finger-shaped

or lobose at end. Stome pentagonal. Jaws unclosed above with

epiphyses. ‘Tooth keeled.

Amongst other points of structural differences, the present species

may be readily distinguished from all other species of the genus by the

presence of very long spines on the abactinal, and of hoof-capped spines

on the actinal side.

Asthenosoma Ijimai, nov. sp.

(Figs. 8-12.)

The following description of this species is based on a single

specimen which was purchased by Prof. Isıma from a Jögashima

fisherman in a fresh state. It was stated that it came up sticking to

the fishing net. The locality of its capture must have been not very far

away from Misaki, but the exact depth is unknown, although we can

safely assert that the particular kind of net used by that fisherman is

never let duwn to a depth beyond 55 fathoms.

Test similar in shape and nature to that of A. longispinum, Yosh.,

but proportionally higher. Diameter 132 mm., height 40 mm. ; color

as preserved in alcohol light yellow with dark brownish spots and

irregular markings.

Plates very numerous. In a vertical row of interambulacral plates

ON TWO NEW SPECIES OF ASTHENOSOMA. 9

there are about 86 plates abactinally and about 26 plates actinally. ‘The

number of ambulacral plates almost twice that of interambulacrals.

Apical system (fig 11) polygonal, projecting. Anus very prominent.

Anal plates (an.) minute, of an elongated shape, few, not reaching anal

margin. Periproctal plates (per.) with pedicellariæ and small spines.

Basal plates (bas.) unclosed, leaving around the genital opening (g.0.) a

narrow membranous tract (bas’.), containing numerous small calcareous

pieces and networks and extending as far down as the 8th.—10th.

plates along the median interambulacral line. Madreporic plate divided

into 4 separate pieces of unequal size (mad.), the largest occupying the

normal position. ‘This division of madreporic plate is probably merely

an individual abnormality.

Ambulacrum straight, 20 mm. wide at ambitus. The arrangement

of ambulacral plates both coronal and peristomal, as also that of the

pairs of pores, essentially same as in the foregoing species.

Tentacles of abactinal side pointed, containing exceedingly minute

calcareous pieces ina small quantity. In the proximity of ambitus,

first the inner tentacles and soon also the outer tentacles begin to be

provided with calcareous discs, as are all on actinal side except those on

peristome. The latter are simply provided with calcareous network.

Tubercles of both ambulacral and interambulacral areas show

marked difference on actinal and abactinal sides.

Primary tubercles of interambulacrum: these appear from the

23rd. plate (counting from periproct) in the proximity of ambitus on

abactinal side, corresponding to the appearance of tentacles with discs.

Down to the 33rd. plate they occur on alternate plates and form a single

row running close to ambulacrum (in., fig. 9). From the 34th. they

occur on every successive plate and form two rows down to the 42nd.

plate. Plates 43rd. to 47th. have alternately two and three primary

tubercles giving rise to five rows (in., fig. 10). Plates 48th. to 55th.

with two primary tubercles each, forming four rows. Finally, plates

56th. to 62nd. with one primary tubercle each, forming two rows.—

Secondary tubercles of interambulacrum : abactinally, up to 10 in a

10 S. YOSHIWARA.

regular transverse row on each plate (in., fig. 9). Actinally, rather

irregularly scattered between primary tubercles (in., fig. 10).

Primary tubercles of ambulacrum: these appear at about the

same level as those of the interambulacrum, in a single interrapted row

along the median ambulacral suture (am., fig. 9). On actinal side

(am., fig. 10) they occur one to each plate but so as to form two regular

rows on the inside of poriferous zone. ‘Towards the peristome, these

rows become more or less interrupted.—Secondary tubercles as on

interambulacral plate, only fewer.

Spines perforated, of four kinds: 1) poison-spines, which are

smooth, pointed and with transverse bands of a brownish color; found

all over the abactinal side, where they may be as long as 16mm., and

also on the peripheral half of the actinal side, where they are mostly

short and do not exceed 7mm. in length; 2) stout, slightly bent,

cylindrical spines, truncated at free end and borne on all primary

tubercles, consisting of crenulated shaft and of simply striated, short,

terminal segment open at end (fig. 12) as long as 22 mm., 3) shorter

spines, covering the main portion of the actinal side, straight, tapering,

cylindrical or shghtly flattened, mostly smooth ; 4) short spines on the

peristome and adjoining parts, club-shaped, curved, flattened, crenulated,

with thick sheath of the soft part.

Pedicellariæ of two kinds: one large and long-headed, the other

small, long-stemmed and trifid.

Branchia with branches that give off numerous, closely set, lobose

branchlets. .

The most prominent feature by which this species can be distin-

guished from all known members of the genus, lies in the peculiar

arrangement of the primary tubercles.

Fig.

yep

ON TWO NEW SPECIES OF ASTHENOSOMA. 1)

Explanation of Plate II.

Asthenosoma longispinum, Yosh.

Portion of abactinal side. Nat. size.

Portion of actinal side. Nat. size.

Arrangement of tubercles on abactinal side. Semi-diagrammatic. in.

interambulacral row ; am. ambulacral row.

Arrangement of tubercles on actinal side. Semi-diagrammatic. Letter-

ing as in foregoing figure.

Portion of periproct and of adjoining coronal plates. Magnified. an.

anal plate ; per. periproctal plate; bas. basal plate ; 9. 0. genital opening ;

mad. madreporic plate; rad. radial plate; in. interambulacrum; am.

ambulacrum. Portions of plates not covered with membrane are shaded.

Adjoining ambulacral (am.) and interambulacral (in.) plates near ambitus.

Magnified.

End of hoof-capped spine. Magnified.

Asthenosoma Jjimai, Yosh.

Portion of profile view. Nat. size.

Portion of abactinal side of test, showing two rows of ambulacral (am.)

and interambulacral (in.) plates. 2.

Portion of actinal side of test, showing two rows of ambulacral {am.) and

interambulacral (in.) plates. x2.

Portion of periproct and of adjoining coronal plates. Magnified. Let-

tering asin fig. 5.

Terminal portion of primary spines, showing the terminal segment and a

small portion of the crenulated shaft. Magnified.

Printed April 30, 1897.

FOA

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DATA.

Annot. Zool. Jap., Vol. I.

Tab. IL.

AWS

Chaetognaths of Misaki Harbor.

By T. Aida.

Zoological Institute, Science College, Imp. Univ., Tokyo.

With Pl. III. § one wood-cut.

During the frequent visits made to the Marine Zoological Station of

the Imperial University at Misaki for the last two years, I have

devoted myself specially to the collection of the chaetognaths to be

found in the harbor. Up to date, I have been able to collect twelve

species in all. The majority of these can not, however, be fished at all

seasons of the year, as their presence depends a great deal on current and

wind. For instance, late in summer last year, when an offshoot of the

Great Black Stream (kuroshiwo) swept into the harbor, many species

not to be seen at other times were caught. I do not therefore think

that the list here given is by any means exhaustive. Other species will

no doubt be added hereafter from time to time.

Of the twelve species mentioned below, four I believe to be new to

science. I have adopted the classification of Langerhans (1), as it

appears most convenient to me.

1. Sagitta bipunctata, Quoy et Gaimard.

(Fig. 1.)

Literature: LANGERHANS (1), Herrwic (2), Grass (3), STRODTMANN (4).

The specimens which I refer to this species present characters

agreeing essentially with the descriptions given by the authors cited

above, the agreement being especially noticeable in the position and

size of the fins, the thickness of the epidermis, the form and position of

the corona ciliata, the length of the body and its ratio to the length of

the caudal segment, the size of the ovaries, and a few other points. But

14 TA GATDA

there are some discrepancies in the number of the seizing hooks and

teeth. Our specimens have 6-7 seizing hooks, 10-12 anterior teeth, and

18-21 posterior teeth, while GRASSI (3) and STRODTMANN (4) give for

European specimens 8-10 seizing hooks, 4—6 anterior teeth, and

10-15 posterior teeth. Thus our specimens have a greater number

of teeth and a smaller number of seizing hooks than those of Europe.

Notwithstanding this difference, Ithink it correct to refer them to the

same species, as they agree in so many other characters.

2. Sagitta serratodentata, Krohn.

(Figs. 2 & 8.)

Literature: Grassr (3), HERTWIG (2), Srroprmann (4).

This species is rare in Misaki, and I caught only three during the

spring of 1896. It resembles closely Sagitta bipunctata, but is distin-

guished from it by its serrated seizing hooks, thinner epidermis and

smaller size.

\ Strodtmann (4) states that the tip of the teeth is distinctly star-

shaped in this species and has at its center the opening of the canal

which runs throngh the body of the teeth. But I was unable to find

such an opening in the teeth of our species, The canal ends at the top

of the teeth blindly and four processes of different size surround the top

(fig. 13).

3. Sagitta hexaptera, D’Orbigny.

(Fig. 3.)

Literature : LANGERHANS (1), HERTWIG (2), Grass (3), STRODTMANN (4).

All the specimens of this species which I have fished are young,

with unripe genital organs. The pear-shaped corona ciliata on the head

segment, the wide lateral field, the number of the seizing hooks and

teeth, and the shape and position of the lateral fins, all point to the

identity of this species with that described by European authors. ,

CHAETOGNATHS OF MISAKI HARBOR. 15

4. Sagitta lyra, Krohn.

(Fig. 4.)

Literature : LANGERHANS (1), HeRTWIG (2), GRASSI (3), STRODTMANN (4).

I fished only a few individuals of this species together with Sagitta

hexaptera during the spring of 1896. The largest specimen I have

caught was 3 cm. long, and its caudal segment 4.5 mm., but its genital

organs were not ripe.

This species has a very wide trunk and a narrow caudal segment,

and two pairs of lateral fins which are continued into each other,

the first pair being long and extending anteriorly to the level of the

abdominal ganglion.

5. Sagitta minima, (Grassi).

(Fig. 5.)

Literature: GRASSI (3), STRODIMANN (4).

This is a small-sized species. The larger individuals reach the

length of 1 cm. and its caudal segment the length of 1.5 mm.

The epidermis is thin. The lateral field is pretty wide. As the

body is widest in the lower part of the trunk and the caudal segment is

comparatively narrow, it is constricted at the border of these two

segments as,in Sagitta lyra. Thetop of the seizing hook is strongly

curved inwards. The ovaries are short, and generally terminate at the

level of the anterior end of the second lateral fin. The corona ciliata

is elliptic and lies wholly on the trunk segment. The intestine is very

wide, nearly filling up the body cavity, and shows here and there trans-

verse wrinkles. It has two diverticula at its beginning.

6. Sagitta enflata, (Grassi).

(Fig. 6.)

Literature : GRASSI (3), STRODTMANN (4).

This species is abundant in Misaki. It can be fished at all seasons

16 T, AIDA.

of the year, though the number differs according to meteorological con-

ditions. ‘The length of the body when fully grown is 12mm. and its

breadth 1.6mm. ‘The caudal segment is 2mm. The anterior pair

of lateral fins lies midway between the abdominal ganglion and the

posterior end of the trunk segment. The second pair is much larger,

and extends along the lower part of the trunk, to the middle of the cau-

dal segment. The eipdermis and the muscular coat are very thin.

The ovaries are small and scarcely reach the upper end of the second

lateral fin. The head is comparatively small, and has 9-10 seizing

hooks, 6-8 anterior teeth, and 10-11 posterior teeth. The corona

ciliata is skein-shaped and lies on the head segment. The ratio of the

length of the caudal segment to that of the whole body is, in our speci-

mens l/,—1/;, thus differing from that given by Grassi, which is !/,.

7. Sagitta neglecta, nov. sp.

(Fig. 7.)

This is the smallest sized species. 'The whole length of the body is

7mm., that of the caudal segment 1.7mm., and the breadth 0.35mm.

The fius are five ; the first pair of fins begin at the posterior end of the

ventral ganglion ; the second pair, which is separated from: the first, is

longer, extending to the middle of the caudal segment. Both lateral

fins are semi-elliptic. The corona ciliata is long, like that of Sagitta

bipunctata, and hes wholly on the trunk segment, never extending to

the head segment between the eyes. Seizing hooks 8; posterior teeth

10-12, anterior teeth 4-5. ‘The top of each tooth has fine processes.

‘he ovaries reach the upper end of the second pair of fins. The sper-

matic vesicle is comparatively large. ‘The epidermis thickens at the

anterior part of the trunk, as in Sagitta bipunctata. The intestine has

two diverticula at its anterior end.

This species is abundant in Misaki throughout the year.

CHAETOGNATHS OF MISAKI HARBOR. 17

8. Sagitta regularis, nov. sp.

(Fig. 8.)

A small-sized species. Larger specimens 7mm. long and 0,5mm.

broad. The caudal segment is nearly */, of the whole length of the

body. The epidermis is thick throughout the entire body, but especially

so in the anterior part of the trunk, so that the head is not constricted

from the body as in other species. The muscular layer is very thick.

The two pairs of lateral fins are separated, and each fin has the shape of

a semi-ellipse. he first fin is short, being nearly half as long as the

second fin which lies mainly on the caudal segment. Seizing hooks 7 ;

anterior teeth 2-4, posterior teeth 5-7.

The intestine has two diverticula at its beginning. The mature

ovaries may extend nearly to the anterior

end of the first lateral fin. The corona

ciliata is long and elliptic, and is on the

trunk segment. The tactile prominences

are well developed and regularly arranged.

---Qg. 4

7 As GRASSI says, there are in all chae-

tognaths two kinds of tactile prominences :

90 os Ge pe

o°09

QeSeo eCe0 00,959 € Ba

one kind is larger, and the hairs, which are

longer than those on the other kind,

60 «O°

are arranged in transverse planes, while

the second kind is smaller and has shorter

hairs arranged in longitudinal planes.

These two prominences are arranged in

this species regularly in alternate trans-

verse rows except in the dorsal and ven-

tral median lines of the body, where the

20) small prominences of the second kind lie

nalongitudinalrow at irregular intervals.

Wood-cut 1.

e=eye, c=corona ciliata,

ag=abdominal ganglion. the dorsal and B the ventral surface,

In the above wood-cut where A shows

18 T. AIDA.

the tactile prominences of the first kind are shown with clear circles and

those of the second with black spots. It may be gathered from the

figures that the number of tactile prominences of the first kind in each

transverse row, is reduced from 6 in the anterior part of the trunk to 4 in

the posterior half, beginning from the level of the first lateral fin. In

each transverse row of the prominences of the second kind 4 lie exactly

between the prominences of the first kind. It must be noted, however,

that the alternation of the rows of prominences of the two kinds

are not rigidly carried out, as sometimes two transverse rows of the

second kind are placed between the rows of prominences of the first

kind. This irregularity commonly occurs in the other species having

a similar arrangement of tactile prominences.

In the caudal segment, the tactile prominences are comparatively

few ; and in the head they are found only on the dorsal surface.

Sagitta bipunctata (small specimens), Sagitta neglecta, Sagitta

minima, Sagitta serratodentata, Krohnia viridis, Krohnia foliacea, and

Spadella draco have all a more or less similar arrangement of tactile

prominences, but none of them shows such a regularity as is found in

this species.

9. Sagitta hispida, Conant.

(Fig 9.)

Literature : Conant (5).

Whole length of the body llmm. that of the caudal segment

2.8mm., and the breadth 0.7mm.

The epidermis thickens at the neck as in Sagitta bipunctata. The

muscular coat is thick and gives the animal a stout appearance. ‘The

two pairs of lateral fins are separated ; the first fin is shorter and begins

slightly behind the abdominal ganglion (in the young, smaller individu-

als, it begins at the middle of the abdominal ganglion) ; the second fin is

longer, extending to the spermatic vesicle. The head is comparatively

large, and has 7-8 seizing hooks, 11-17 posterior teeth, and 7-8 ante-

rior teeth. Our specimens have a greater number of seizing hooks and

CHAETOGNATHS OF MISAKI HARBOR. 19

teeth than that described by Conant. The corona ciliata is long, ex-

tending anteriorly between the eyes to the base of the brain. It does

not reach posteriorly, in our specimens, to the level of the abdominal

ganglion, as described by Conant. The intestine has two diverticula at

its beginning. The tactile prominences are very numerous and are

arranged somewhat like those of Sagitta hexaptera.

10. Krohma foliacea, nov. sp.

(Figs 10&16.)

The essential characteristic of this species lies in the possession of a

single pair of lateral fins of remarkable size. It extends from before the

abdominal ganglion to the middle of the caudal segment, and its breadth

is nearly equal to that of the trunk. Along its margin the tactile pro-

minences are arranged symmetrically in both fins at more or less regular

intervals. The body is llmm. long, and the caudal segment nearly

1/5 as long. The epidermis and the muscular coat are thick just as in

Sagitta bipunctata, comparing individuals of equal size. At the anterior

part of the trunk segment there is a thin but well marked transverse

muscular layer on the ventral side. The corona ciliata is flask-shaped,

and lies on the head segment.

Seizing hooks 7, and the single row of teeth, which corresponds

to the posterior row in other chaetognaths consists of 5 teeth. The

top of the seizing hook is strongly curved inwards (fig 16).

I caught only two specimens of this species in the spring of 1896,

and as both were young, with unripe genital organs, I can not give

further descriptions.

11. Krohnia pacifica, nov. sp.

(Figs. 11, 14, & 15).

This species can be easily distinguished by its faintly yellowish-

green epidermis and the ovaries of the same color. One mature

20 T. AIDA.

specimen measured 6mm. in length * and 0,33mm. in breadth, and its

caudal segment 1.8mm. The head is comparatively small and has 9

seizing hooks and 10-11 teeth arranged in a single row. The row of

one side meets at the top of the head with that of the other side (fig 14,

a). Hach seizing hook has a simple termination like that of Krohnia

subtilis (fig 15). The fins are three ; a single pair of lateral fins extend

from before the spermatic’vesicle to the level of the anterior end of the

ovary, and lies equally on the trunk and caudal segments. The caudal

fin is narrow and long, its breadth being nearly one half of its length.

It is attached anteriorly to the spermatic vesicle. The corona ciliata is

elliptic and lies wholly on the trunk segment. The mouth is a transverse

slit.

This species greatly resembles Krohnia subtilis, but is distinguished

by its small head, regular row of teeth, the smaller number of the teeth,

and some other characters.

12. Spadella draco, (Krohn.)

(Fig 12.)

Literature : LANGERHANS (1), Herrwie (2), Grassi (3), STRODTMANN (4).

This is the only species of Spadella ever fished in Misaki Harbor.

The wide lateral epidermoidal extension of the large vesicular cells, a pair

of large tactile prominences, a pair of lateral fins, two rows of teeth, etc.

distinguish it from other species.

In conclusion, I wish to tender my thanks to Prof. Dr. K. Mrrsu-

KURI for valuable advice and aid.

* Among the chaetognaths from the Bonin Islands, collected by the late Mr. Hrrora,

I found one specimen of this species, which differs, however, from those of Misaki in

some points. Itis a young individual, but its body is 13mm. long. The corona ciliata

is more elongated posteriorly, like that of Sagitta neglecta. The lateral fins extend on

the trunk segment nearly one half as much as on the caudal segment.

CHAETOGNATHS OF MISAKI HARBOR. 21

LITERATURE.

(1). LANGERHANS, P.—Wurmiauna von Madeira III Zeitschr. für wissensch.

Zoologie. Bd.34, p. 132—136. 1880.

(2). Herrwie, O.—Die Chaetognathen, eine Monographie. Jenaische Zeitschrift

für Medicin und Naturwissenschaft, 1880.

(3). Grassı, B.—I Chetognathi. Anatomia e sistematica con aggiunte embriolo-

giche. Fauna und Flora des Golfes von Neapel. 1883.

(4). STRODTMANN, S.— Die Systematik der Chaetognathen. Archiv für Natur-

geschichte, Jahrgang 58, Bd. 1, 1892.

(5). Conant, F. S.—Description of Two New Chaetognaths. The Johns Hopkins

University Circular, no. 119, June, 1895.

(6). Conant, F. S.—Notes on the Chaetognaths. The Annals and Magazine

of Natural History, 6. series, vol. 18, no. 105, 1896.

EXPLANATION OF FIGURES.

Fig. 1. Sagitta bipunctata.

2 Sagitta serratodentata.

3. Sagitta hexaptera.

4. Sagitta lyra.

5. Sagitta minima.

6. Sagitta enflata.

ff Sagitta neglecta.

8. Sagitta regularis.

9. Sagitta hispida. d

10. Krohnia foliacea.

11. Krohnia pacifica.

12. Spadella draco.

13. Teeth of Sagitta serratodentata.

14. (a) Ventral view of the head of Krohnia pacifica. (b) Its teeth.

15. Seizing hook of Krohnia pacifica.

16. ‘lop of the seizing hook of Krohnia foliacea.

Printed April 30, 1897.

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SANITOSHA ,E NG.,SHINACAWA

On the Accommodation of Some Infusoria to

the Solutions of Certain Substances

in Various Concentrations.*

(Preliminary Note.)

By Atsushi Yasuda.

Botanical Institute, Science College, Imp. Univ., Tokyo.

Organisms are generally influenced by external circumstances, and

when the medium, in which they are found, is changed they, to a certain

extent, accommodate themselves to the new one. About this faculty a

number of investigators have already contributed’ to our knowledge

many interesting facts, various media and organisms having been

submitted to observation.

Among lower plants, SrtARL” studied the accommodation of some

myxomycetes to grape-sugar solutions. KLEBS” noted the recovery of

fresh-water algæ from the plasmolysis caused by solutions of some

chemical substances, and in this way established to some extent their

power of adaptation to the new media. RICHTER” made some detailed

experiments on the accommodation of fresh-water alge to common-salt

solutions. The same result as that found by KLEBS was observed by

JANSE” with fresh-water and marine alge, and also by OLTMANNS” in

* Reprinted, with the author’s approval, from the Botanical Magazine, Tokyo, Vol. XI,

No. 121, published March 20, 1897.

1) E. Srauu. Zur Biologie der Myxomyceten. Bot. Ztg., 1884 Nr. 10, p. 166.

2) G. Kuess. Beiträge zur Physiologie der Pflanzenzelle. Berichte der deutsch.

bot. Gesellsch., 1887. Bd. V, Heft 5, p. 181.

3) A. Ricuter. Ueber die Anpassung der Siisswasseralgen on Kochsalzlösungen.

Flora, 1892, p. 4.

4) J. M. Janse. Plasmolytische Versuche an Algen. Bot. Centralbl., 1887. Bd.

XXXII, p. 21.

5) F. Orrmanns. Ueber die Bedeutuug der Concentrationsänderung des Meerwas-

sers für das Leben der Algen. Sitzb. d, Königl. preuss, Akad. ds Wissensch. zu Berlin,

1891, p. 193.

24 A. YASUDA.

the case of marine algæ. EscHENHAGEN” showed the effects of various

solutions on the growth of some moulds.

Concerning higher plants, WIELER observed in one case” the

recovery of Vicia Faba and Phaseolus multiflorus from the plasmolysis

caused by sugar solutions, while in the other case” he noticed the

deformation of the roots of the latter plant when put into glycerine

solutions. STANGE” showed in his “ Beziehungen zwischen Substratcon-

centration, Turgor und Wachsthum . bei einigen phanerogamen

Pflanzen ” the adaptation of Phaseolus vulgaris, Pisum sativum, and

Lupinus albus to plasmolyzing agents. TRUE” experimented upon the

influence of a sudden change of turgor on the growth of Vicia Faba.

In the animal world, SCHMANKEWITSCH® came to the conclusion

that Branchipus stagnalis which lives in fresh-water, changes into

Artemia Milhausenti in brackish water, and then again into Artemia

salina in salt-water. That the larve of sea-urchins are also deformed

by various solutions of chemical substances has been shown by the ex-

periments of HERBST.”

There is no doubt that infusoria are like other organisms, also

influenced by change in the concentration of the substratum, and within

a certain limit, a more or less accommodation to the new medium takes

1) F. EscHenHAGEN. Ueber den Einfluss von Lösungen verschiedener Concentration

auf das Wachsthum von Schimmelpilzen. Stolp. 1889.

2) A. WIELER. Plasmolytische Versuche mit unverletzten phanerogamen Pflanzen.

Berichte der deutsch. bot. Gesellsch., 1887, Bd. V, p. 378.

3) A. WIELER. Ueber Anlage und Ausbildung von Libriformfasern in Abhängiskeit

von äusseren Verhältnissen. Bot. Ztg., 1889, Nr. 34, p. 551.

4) B. Stange. Beziehungen zwischen Substrateoncentration, Turgor und Wachsthum #3

bei einigen phanerogamen Pflanzen. Bot. Ztg., 1892, Nr. 18, p. 292 und Nr. 19, p. 307.

5) R. H. True. On the Influence of Sudden Changes of Turgor and of Temperature

on Growth. Annals of Botany, 1895, vol. IX, p. 372.

6) W. ScHMANKEWITSCH. Zur Kenntniss des Einflusses der äusseren Lebensbedin-

gungen auf die Organization der Thiere. Zeitschr. f. wiss. Zool., 1877, Bd. XXIX, p. 429.

7) ©. Herest. Experimentelle Untersuchungen über den Einfluss der, veränderten

chemischen Zusammensetzung «des umgebenden Mediums auf die Entwicklung der "A

Thiere. I. Theil. Zeitschr. f. wiss. Zool., 1892, Bd. LV, p. 446.

ACCOMMODATION OF INFUSORIA TO CERTAIN SOLUTIONS. 25

place. But then, to what extent would they accommodate themselves

to that medium ? And again, what change is brought about to the bodies

of these organisms ? Con”? observed in his early investigations ‘that. a

sudden change of the concentration of the medium was injurious or fatal

to them. FABRE-DOMERGUE? noted that the reserved materials found

in the bodies of infusoria appeared and disappeared according as the ex-

ternal conditions might be favourable or unfavourable to them. : BokoR-

ny? found certain changes in their bodies when subjected to the action

of some basic substances. But a more detailed study on the effects ‚of

the changed medium upon them has not yet been made.

I began to investigate this subject from the spring of last year in

the Botanical Institute of the Imperial University, and will now make

a preliminary note of some of the results of my experiments.

I selected milk-sugar, cane-sugar,” grape-sugar, glycerine, and com-

mon salt as the external media to be used, while the iufusoria Colpidium

colpoda, Chilomonas paramecium, Euglena viridis, Paramecium

caudatum, and Mallomonas sp. were chosen as bodies for the investigation.

The experiments now described were made by a sudden transfer of

the organisms from the normal medium to an abnormal one, those in

which gradual change of the concentration of the medium is made being

still in course of investigation, and it may be proved to be the case that

the degree of accommodation given here is in reality much lower than

that when gradual change is made.”

1) F. Coun. Entwickelungsgeschichte der microscopischen Algen und Pilze. Nova

Acta Akad. Ces. Leopold., 1854, Bd. XXIV, Th. 1, p. 132. (Cited by TRUE.)

2) M. Fagre-DomerGue. Recherches anatomiques et physiologiques sur les infusoires

ciliés. Annales des sciences naturelles, Zoologie, 1888, 7me série, tome V, p. 135.

3) T. Boxorny. Einige vergleichende Versuche tiber das Verhalten von Pflanzen und

niederen Thieren gegen basische Stoffe. Pfliiger’s Archiv fiir die gesammte Physiologie

des Menschen und der 'liere, 1895, p. 597.

4) As our culture of infusoria contained bacteria it was necessary to test how long

cane-sugar was recognisable as such in the culture-water. After four days I found, by

means of Fehling’s solution, that a little inversion of it had taken place.

5) F. EscHENHAGEN,. loc. cit. p. 34. Also B. STANGE. loc. cit. Nr. 18, p. 293.

26 A. ‘YASUDA.

‘ Phe examination of each culture was made at the end of 1-5 days,

was repeated several times, and every time carefully compared with the

control-culture.

Colpidium colpoda.

In milk-sugar solution the organism was found to survive in 1-

10% :concentrations. In 1-2% solutions nothing remarkable was

observed, but in a 4% solution the vacuoles increased in size and ihe

body enlarged itself and became somewhat rounded. In solutions above

6% the vacuoles greatly enlarged and increased in number, giving the

body of the organism an extremely plump appearance.

In the case of cane-sugar the organism survived in 1-8% solutions.

In a 3% solution the vacuoles became larger and the body began to be

rounded. In solutions above 5% these changes were more noticeable.

In grape-sugar it survived in 1-7% solutions, and behaved much as

in the preceding medium.

In glycerineit was found to survive in 1-5% solutions, changes like

the last being produced by solutions of 3% and stronger.

In common salt it survived up to 4% solution.

Chilomonas paramecium.

The organism survived in 1-8% milk-sugar solutions. In a 4%

solution the corpuscles became larger and the body increased both in

breadth and thickness while it rather decreased in length. In an 8%

solution these changes were the most remarkable.

Of the 1-7% cane-sugar solutions in which it could survive, those

above 3% produced changes on its body like those caused by milk-sugar.

This organism seemed to adapt itself well to 16% grape-sugar, 1-4%

lycerine, and -,-2% common salt.

SAS , 0m 0)

Euglena viridis.

Solutions of 1-17% milk-sugar, 1-13% cane-sugar, 1-11% grape-

sugar, 1-5% ? glycerine, and more than 2% common salt were found to

ACCOMMODATION OF INFUSORIA TO CERTAIN SOLUTIONS. 27

be suitable to the life of this organism. Its body is highly metabolic,

so that no distinct change except the enlargement of the corpuscles

could be observed.

Paramecium caudatum.

This organism was found to survive in 1-8% milk-sugar, 1-7%

cane-sugar, 1-5% grape-sugar, 1-3% glycerine, and ~;>-}% common

salt solutions, and experienced changes similar to those observed in the

case of Colpidium colpoda.

Mallomonas sp.

Solutions of 1-9%milk-sugar, 1-7% cane-sugar, 16% grape-sugar,

1-4% glycerine, and ~,-3% common salt were adapted to this organism,

and had the usual effects.

In general, when the concentration of the external medium increas-

ed, the bodies of the organisms contracted, and then their movements

which had hitherto been active became slower and slower until they

ceased entirely. In a few hours, however, the contraction of their bodies

gradually disappeared and they recovered their normal condition, accom-

modation to the new medium now beginning to take place. Similarly,

FiscHER” found that 10-30% cane-sugar, which caused strong plasmo-

lysis on Spirillum, stopped its movement. Ewart” also observed that

Bacterium Termo, which moved actively in 10% cane-sugar or 5%

grape-sugar, lost its activity in 20% cane-sugar or 10% grape-sugar,

and finally came to rest in 30% cane-sugar or 20% grape-sugar.

The higher the concentration of the solutions, the more difficult the

accommodation of infusoria to them became, and when it took place the

vacuoles or the corpuscles in the bodies of the organisms remained

1) A. FiscHer. Untersuchungen über Bakterien. Pringsh. Jahrb., 1895, Bd. XXVII,

pp. 39—40. :

2) A. J. Ewarr. On Assimilatory Inhibition in Plants. The Journal of the Linnean

Society, 1896, vol. XXXI, no. 217, p. 434.

28 A. YASUDA.

increased in size as well as in number while their bodies became much

thicker, with outlines presenting a more or less rounded appearance.

Of the five external media I used the sugar-solutions proved to be

the best adapted to the organisms, the highest degree of adaptation

being possessed by milk-sugar, then followed cane-sugar and next grape-

sugar. Glycerine was found to be better adapted than common salt.

It is evident that the action of the above substances is not due to

the degree of their concentration but to their chemical nature ; for the

solutions which were in isotonic concentration did not have the same

effect upon the organisms. Thus, in the cultures of Colpidium colpoda,

for example, 8% cane-sugar, which is isotonic with 8.4% milk-sugar,

4.2% grape-sugar, 2.2% glycerine and 0.9% common salt, formed the

highest limit, together with 10% milk-sugar, 7% grape-sugar, 5%

glycerine and 4% common salt, so that the limits in the latter case were

generally found to be far higher than those in the former, except with

common salt where, on the contrary, the adaptation of the organism

was much lower. A similar observation was made by STANGE,” who

found that isotonic solutions caused various growth-rates in the bodies

of plants.

Conclusions :—

(1) Isotonic solutions of the chemical compounds in question do not

produce corresponding effects upon the bodies of infusoria. The action

depends more upon the chemical nature of each substance than upon

its concentration.

(2) In solutions of higher concentration a contraction of the bodies

takes place, which disappears after some hours, when the organisms

begin to accommodate themselves to the new media.

(3) Higher concentration of the medium retards the multiplication

of the organisms,

(4) As the concentration of the medium ingreases, the movement of

the organisms is retarded.

1) B. Stange. loc. cit. Nr. 22, p. 364.

ACCOMMODATION OF INFUSORIA TO CERTAIN SOLUTIONS. 29

dle

(5) In sugar-solutions of higher concentration some infusoria seem

to increase in size, only till a certain limit is reached.

(6) The vacuoles or the corpuscles increase in diameter as the con-

centration of the medium becomes stronger.

(7) The more the concentration of the medium increases the more

rounded become the organisms.

March 1897.

Reprinted May 6, 1897.

WANG MLE TROVA

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On Changes which are found with Advancing

Age in the Calcareous Deposits of

Stichopus japonicus, Selenka.

By K. Mitsukuri, Ph. D.

Professor of Zoology, Imp. Univ., Tokyo.

I am at present engaged in a study of the Holothurioidea of Japan,

the results of which I hope to publish elsewhere before long. But the

following facts in regard to the calcareous bodies of our commonest

holothurian —Stichopus japonicus, Selenka,—appear to me remarkable

enough to deserve a separate preliminary notice.

The statements made by previous writers about the calcareous

bodies of that species do not in many respects agree with one another,

and it will be found difficult to obtain from them a clear idea on the

matter. This is not to be wondered at, as some most important ‘facts

have hitherto been entirely overlooked.

SELENKA who gave the first description of the species (Zeitsch. für

wiss. Zool., Bd. XVII, p. 318) had only one specimen 110 mm. long. ‘In

Rig. 1 regard to the calcareous bodies, he says ;

“Die Kalkgebilde bestehen ausschliesslich

34 35 36 in 0.05mm. breiten thurmförmigen Körper

ak 0025 (Fig. 34-35), unter denen ich sehr zahlreiche

Je)

Hemmungsbildungen, nämlich durchbroch-

Caleareous bodies 9 ene Ringe, finde (Fig. 36). ”

Stichopus japonicus. Copied Ù

from SELENKA. Von MARENZELLER who next touched

on the subject (“ Neue Holothurien von Japan und China, ” Verhandl.

zoolog-bot. Gesellsch. Wien, 1881, p. 137) had several specimens;; the

largest of which was 70 mm. long and not sexually ripe. He says :—

“Die Kalkkôrper sind, wie SELENKA angiebt, von den Kalkstaben der

32 K. MITSUKURI.

Füsschen abgesehen, nur einerlei Art. Die Fig. 35 (SELENKA, J. c.)

gibt wohl nur eine Hemmungsbildung wieder, die dadurch entstanden,

dass die Stäbchen des Stieles nicht gleichmässig zur Ausbildung kommen,

und mit einander vor der Bildung einer Krone verschmelzen. Uebrigens

habe ich eine solche Form nie gesehen. Fig. 11a* stellt eine regelmässe

kleine, Fig. 11 * eine grosse Scheibe dar. Die Scheibe der Stühlchen

misst in Durchmesser nicht leicht unter 0.045 mm. und selten 0.075 mm.

Dazwischen alle Grössen. Ich finde den Stiel nicht durchaus so gebildet,

wie ihn SELENKA unter Fig. 34 wiedergibt. Er ist hier breit und

zeigt nur einen einzigen Querstab unter der Krone, deren Zacken übri-

gens zu stark nach aussen gebogen scheinen. Neben solchen Stühlchen,

an welchen der an der Basis z. B. 0.18 mm. breite und 0.033 mm. hohe

Stiel gegen das Ende immer verbreitert ist, finden sich andere noch von

gleicher Gestalt, aber mit zwei Querstäben im längeren Stiele, und dann

durch Uebergänge verbunden solche, deren Stiel schmal, lang, mit zwei

und mehr Querstäben versehen und etwas konisch zulaufend, nicht

verbreitert ist. * * * * Ferner kann die Zahl der Stäbchen des

Stieles reducirt werden. Ich fand ein Stühlchen mit einem 0.09 mm.

langen und 0.015 mm. breiten Stiele, der fünf Quertäbe aufwies, aber aus

nur zwei Langsstäben bestand.” No mention is made by v. MAREN-

ZELLER of the presence of such perforated plates as are given in SELEN-

KA'S fig. 36.

THEEL in his Report on the Challenger Holothurioidea (Reports,

vol. XIV) had one specimen of Stichopus japonicus, and says: “ The

specimen does not quite agree with the description of SELENKA and von

MARENZELLER, but nevertheless, I do not think it possible to refer it

to any other species. * * * * Itis especially with regard to the

deposits that disagreements exist, which render the correctness of my

determination dubious. The tables have the same shape as described

by von MARENZELLER (Pl. VIL, fig. 3, a, d.) but, besides these, I find

a great quantity of small rounded or oval perforated plates (PI.

* Von MARENZELLER’s figs. Il a and b are very much like Fig. 2 a, b, of the present

article.

ON THE CALCAREOUS DEPOSITS OF STICHOPUS JAPONICUS. 33

VII, fig. 3, c) some of which bear a certain resemblance to buttons.

SELENKA also described such bodies under the name of ‘ Hemmungs-

bildungen’. ”

THHEL had two other specimens each 220 mm. long which he

established into a new variety under the name of Stichopus japonicus,

var. typicus. In regard to the calcareous bodies of these specimens, he

found that they consisted of tables alone, but comparatively few of them

were fully developed, by far the greater part presenting themselves

under the shape of perforated discs with the margin very uneven or

spinous, and with no spire or a very poorly developed one. The rare

complete tables were smaller and larger, composed of a rounded per-

forated disc with smooth margin and a spire built up of mostly four

rods, with one or more transverse beams, and often terminating in four

longer or shorter teeth. There were also found tables with a spire com-

posed of only two rods. It is but just to THÉEL to mention that he

makes a distinct statement to the effect that, these specimens may

prove to be older and more developed forms of Stiehopus japonicus than

those previously studied.

LAMPERT in his “ Die Seewalzen ” says : “‘ Stiel der Stühlchen bald

mit einer, bald mit zwei Querleisten, in letztem Falle oft mit seitlichen

Dornen besetzt; die als durchbrochene Ringe erscheinenden Hem-

mungsbildungen sehr zahlreich. ” He also says ‘‘ einspitzige Stühlchen

wie SELENKA eines abbildet, konnte ich eben so wenig wie v. MARENZEL-

LER auffinden. ”’

To make the matter still more intricate, the form which SELENKA

(2. e.) described under the name of Holothuria armata and in which he

found only sparingly “ durchbrochene Plättchen ” besides the “ End-

scheiben, ” is considered by THÉEL to be probably nothing else than

Stichopus japonicus (Challenger Report, Vol. XIV, p. 196).

From these citations, we are able to gather the fact that the calca-

reous deposits of Stichopus japonicus consist of only one kind, viz.

tables. But beyond this, it is difficult to obtain any clear ideas. It is

most probable that these tables are present in the shape of simple per-

34 K. MITSUKURI.

’

forated plates as ‘ Hemmungsbildungen,” but von MARENZELLER

makes no mention of them. As to what the shape ofthe complete

tables is, one will be sorely puzzled to find out. The figures and de-

scriptions given by SELENKA and by LAMPERT will be found difficult to

reconcile with those of VON MARENZELLER or of THEEL. Moreover,

while it seems certain that there are forms closely related to Stichopus

japonicus, such, for instance, as that described by THÉEL as var. typicus,

or that called by SELENKA Holothuria(or Stichopus according to THKEL)

armata, it is impossible to know exactly in what relation these forms

stand to the species proper or to one another. .

When I began to examine the specimens of what I supposed to be

Stichopus japonicus my perplexity was greatly increased. For actual

specimens seemed to be about as varied as the descriptions of the above

mentioned authors. Individual after individual were found with only

perforated plates * and without any complete tables. Or if I succeeded

in finding some with complete tables, these latter seemed to show a

great variety of forms among themselves, so that it was impossible to

specify a shape common to all specimens. Finally, the question seem-

ed to resolve itself into this : Hither there are two distinct species among

the form known in Japan as the common “ namako” (hitherto supposed

to be identical with Stichopus japonicus), one species corresponding to

Holothuria armata of SELENKA and the other to Stichopus japonicus of

the same author, or else the species known as Stichopus japonicus,

Selenka, presents an extraordinary variety of forms in their calcareous

deposits. If the former alternative was the case, it was most desirable

to establish the fact and to define the limits of each species, for it had a

most practical bearing on the question which it had been, and is, my

purpose to study, viz. how to protect or cultivate the namako for

economic purposes. If the latter alternative was the case, it would be

of great morphological interest to find out with what conditions, these

variations of the calcareous deposits are correlated. To settle the ques-

* Apart from the terminal dise and supporting bodies of the tube-feet and papille.

Of these, I am not at all speaking in the present article.

ON THE CALCAREOUS DEPOSITS OF STICHOPUS JAPONICUS. 35

tion in either way, the overhauling of a large number of specimens of

both sexes, at various stages of growth and from all sorts of localities

was a necessity. Fortunately, I had been slowly accumulating just

such a collection, in course of the inquiry undertaken with the

above-mentioned economic object at the request of the Ministry of

Agriculture and Commerce. Moreover, from the experience thus

gained, I found it possible to tell within certain limits the age of a

’

given “namako” and obtained the knowledge of when and where

individuals of certain sizes might be found.* I thus flattered myself

that I had favorable opportunities for settling the question put forth

above in regard to the calcareous deposits of the “ namako. ”

I shall now briefly set forth the results of my study on this ques-

tion :—-

The holothurians commonly known in Japan under the name

of the “namako ’

all belong to one species, viz.:—Stichopus japo-

nicus, Selenka. The form distinguished by THÉEL as var.

typicus is only a stage in the growth of the species. Holothuria

armata, Selenka may possibly be better set down as a variety of

this species, not, indeed, on account of its calcareous deposits but

of some other characters——as will become clear in the sequel.

The form of calcareous bodies + changes with advancing age in

Stichopus japonicus. The youngest individuals have most perfectly

formed, large-sized tables and nothing but these. They have such

tables very thickly crowded or even overlapping with their bases.

With the growth of the animal, perfectly formed tables decrease

both in number and size, and tables in various stages of arrested

development are found mixed with them. The degree of imperfec-

tion in tables of arrested development as well as the proportion of

such tables to perfectly formed ones constantly increase with age,

* It is my intention to put together elsewhere the results of my inquiry into the

habits and life-history of the “ namako,” together with my plan for the propagation of

the animal.

+ As before, I am not speaking of the terminal discs and supporting rods of the

tube-feet.

36 K. MITSUKURI.

until in fully grown individuals, there are found nothing but small

perforated plates, representing only a small central part of the

basal disc and without any trace of the spire. These are moreover

comparatively but thinly scattered in the skin.

As the changes outlined above take place only by degrees, it is not

of course possible to fix any well marked stages ; nevertheless as a matter

of convenience in describing and identifying various steps in the changes,

I have ventured to assort individuals in various stages of growth into

five groups as follows :—

Stage I:—Includes the youngest individuals whose caleareous bod-

ies are all well formed tables. The preparations* made from specimens

Fig. 2.

di)

)

respectively 10, 18, 23, 27 and 30mm. iong + present a striking appear-

ance. The skin is so thickly crowded with tables that very little space is

left between them. These tables (fig. 2) have all a well formed basal

disc and a tall slender spire, and are tolerably uniform in size, com-

pared with those found in later stages. The commonest size of the basal

disc is about 0.06 mm. but exceptionally large ones may reach 0.11—

or even 0.12 mm. when measured along the longer axis of those that

* Made by simply passing a piece of the thin and almost transparent skin through

different grades of alcohol, clarifying it in clove-oil and then mounting it in balsam,

without any treatment with potash.

+ All measurements made in alcoholic specimens, unless otherwise specified.

ON THE CALCAREOUS DEPOSITS OF STICHOPUS JAPONICUS. 37

have an oval disc. Those below 0.06 mm. are comparatively few, at least

in the youngest individuals. They all possess a smooth margin. The

four pillars of the spire are set very close to one another in the center

of the disc. The commonest number of transverse beams are three or

four, but exceptionally may become five or two. The pillars often incline

towards one another, above the highest transverse beam but one, so

that the spire frequently looks as if it were slightly conical or ended in a

point. There are minute teeth on the spire, especially near the tip.

The height of the spire is generally about 0.06 mm. but may become

slightly higher (0.078) or lower (0.048).

In older individuals of this group—e. g. in those respectively 39,

40, 46, 50, 60 mm. long—the tables whose disc is less than 0.06 mm.

sometimes becoming as small as 0.03 mm. are mixed with larger ones in a

greater proportion than in younger individuals. Many of these discs

have only eight holes è. e. four small holes in addition to, and alternating

with, the four large holes at the center. Those with only the four

central holes (fig. 3) which are such a prominent feature of later stages

are as yet very rare, and even these have a tolerable spire. The height

of the spire seems also in many cases somewhat reduced, and those with

two transverse beams are of much more frequent occurrence. The

tables are also much less closely scattered than heretofore. One indi-

vidual 70 mm. long I feel justified in placing in this group, for although

the features given above for the individuals that are 39-60 mm. long

in contrast to younger individuals are brought out still more prominent-

ly, nearly all the tables have still some sort of spire, even if the spire

has often only one transverse beam, or may consist of only three or two

pillars.

We may therefore conclude that young individuals whose lengths

are below about 70 mm. possess calcareous bodies which are all well

formed tables.

It is evident that the specimens which vow MARENZELLER examin-

ed, belonged to this group, for the largest one in his possession measured

70mm. This circumstance accounts for the fact that he males no refer-

38 K. MITSUKURI.

ence to those perforated plates or ‘ Hemmungsbildungen ” which

others mention as an important feature.

Stage II:—In this group, I propose to include those individuals in

which those small, perforated plates with or without rudiments of a

spire (fig. 3) begin to be a noticeable feature but not to such an extent

that they seem to form a larger portion of the calcareous deposits of the

animal than the well formed tables. I have fixed a somewhat arbitrary

standard and put in this group all those in whose skin I could count at

least 7-10 well-built tables (fig. 2) in a field, when examined with Zeiss

CC x8. The tables with 2-3 transverse beams are most frequent.

Some with only one beam are seen.

It is impossible to fix any limits in the lengths of individuals belong-

ing to this group with anything like accuracy. Those which I have

placed in this group are respectively 50, 50 54, 70, 70, and 110 mm. in

lengths.

I believe that the single specimen which THEEL identified with

some hesitation as Stichopus japonicus, belongs to this stage. His de-

scription tallies well with what I have given above.

Stage III:—This I propose to call the typicus stage, for those speci-

mens which THÉEL distinguished as Stichopus japonicus, var. typicus

may be taken as good examples of this stage. Here the calcareous

bodies which correspond to the large well formed tables of the preceding

stage have begun, many of them, to show various degrees of imperfec-

tion. ‘This arresting of development affects both the basal disc and the

spire. Thus the spire may become lower, have a smaller number of

transverse beams (1-2), and often have the ends of the pillars bent out-

wards (SELENKA, Fig. 34, or THEEL, pl. VIII, fig. 20). Or the pillars

may be reduced in number to three or two, or be occasionally increased

to five (THÉéez, pl. VIII, fig. 2d), and often inclined towards one

another, especially near the upper end so as to produce a conical shape.

Or the spire may be represented by 1-4 simple knobs which are rudi-

ments of the pillars. Or finally there may be no trace of a spire. The

complete tables have the margin of their basal disc entirely smooth, but

ON THE CALCAREOUS DEPOSITS OF STICHOPUS JAPONICUS. 39

the discs that are affected by the “ Hemmungsprozess ” have all more

or less spinous margin and are reduced in size in various degrees. (See

THEEL, Pl. VIII, Eig. 2d.) When no spire is developed a table be-

comes nothing but irregular perforated plates with spinous margin.

The larger ones of this kind graduate by degree into small, perforated

plates which we saw in the preceding stage. At this period, therefore,

we see three kinds of calcareous deposits: (a) completely built tables

such as we saw in Stage I, (b) tables showing various degrees of imper-

fection and having spinous margin, and (c) perforated plates, mostly with

spinous margin which from tolerably large ones shade off into quite

small quadriloculate forms.

The specimens which showed best the characteristics of this stage

are several individuals 200-250 mm. long (in fresh state), which I obtained

at Kanagawa and which I believe, from a series of observations made at

the same locality, to be at the end of their first year. There are, how-

ever, others which are smaller (175 mm. fresh. Tokyo market) and larger.

THEEL’S specimens measured 220 mm. and must have been considerably

larger in fresh state.

Stage IV:—This is the stage in which the original specimen de-

scribed by SELENKA must have belonged, although it was only 110 mm.

in length. The tables of the original form which were characteristic of

Stage I, have now all disappeared or, if present, very rare, and only those

that show various degrees of imperfection are seen and even these are

not very numerous. The spire is mostly very low, having generally

only one or at the most two transverse beams, and may be reduced in

the number of the pillars. Various forms of asymmetry* may be pro-

duced by difference in lengths of the pillars on the same disc, or by the

pillars inclining towards and fusing with, one another. SELENKA’s Fig.

35 represents without question one of these forms, and I have seen many

which are quite near it, although never one which is exactly as symme-

trical as the one the figure shows. By far the most prominent feature

* Such forms may also be seen from earlier stages.

40 K. MITSUKURI.

Fig. 3. of the calcareous deposits in in-

dividuals of this stage is the pre-

SONDA © ZO

GS (@ eg 109 sence of those which SELENKA

named “ Hemmungsbildungen ”

& SY 63) I (Fig. 3). These show various

g < sizes, but on the whole are small-

Some forms of perforated plates. er than those in the typicus stage.

263, On many are seen little knobs

which are the rudiments of the pillars of a spire.

It is impossible to give any limits in the lengths of individuals

which belong to this stage. Those that I placed here range between

50 mm. (alcoholic specimen) and 210mm. (in fresh state). Probably still

larger ones may be placed here.

Stage V:—This I propose to call the armata stage, for the speci-

men which SELENKA named Holothuria armata, had calcareous bodies

which are typical of this stage. In other words, all forms of tables with

a spire have now entirely disappeared. At the most, there are only

simple knobs which represent the rudiments of the pillars of a spire.

All the calcareous bodies are therefore in the shape of perforated plates

or SELENKA’S “ Hemmungsbildungen.” In the younger ones of this

stage, these perforated plates may be still large aud have spinous margin,

but the older the individual, the smaller and smoother become the cal-

careous bodies, aud the nearer they approach the shape. of a ring with

four openings, representing the four central holes in the dises of the earlier

tables. In the very oldest, even these four holes are not complete, and

a part of the circumference may often be lacking to the ring. The

calcareous deposits are also much more sparsely distributed than in

earlier stages.

I need hardly remind the reader that as the above five stages have

been artificially marked out in an unbroken series of changes, many an

intermediate state of things will be found, which an investigator will

find difficult to put precisely in any one of them. I claim for them

nothing beyond some advantage that they afford in elucidating the

ON THE CALCAREOUS DEPOSITS OF STICHOPUS JAPONICUS. 4]

the process of changes in the calcareous deposits of Stichopus japonicus.

It is evident from what has been given above that the calcareous

deposits in our species are more complete and show more primitive

characters in young stages than in older or adult forms. In the young-

est stages examined, they have almost the character of a calcareous coat

of armor, similar to that of a starfish or of a sea-urchin. There are un-

doubtedly physiological reasons for this : the youngest individuals have a

very thin and pliable skin and muscle layer so that some sort of protec-

tion and support is a necessity. But a possible phylogenetic signi-

ficance should not be lost sight of.

It will be seen that I agree with THEEL in regarding Holothuria

armata of SELENKA to be only a form of Stichopus japonicus. My rea-

sous for thinking so are as follows :—I have fortunately some specimens of

Holothuria armata which Prof. SELENKA kindly identified for us during

his stay in Japan. There can be therefore no question as to their being

Holothuria armata. Now, an examination of the calcareous deposits of

these specimens reveals a condition exactly like the fifth stage of Stecho-

pus japonicus. I see no reason for separating them from other speci-

mens of Stichopus japonicus of the same stage, so far as the calcareous

deposits are concerned. Unfortunately, these specimens lack the viscera,

and I have not yet had an opportunity of examining the reproductive

organs of this type. But my friend, Mr. Nozawa of the Hokkaido

Fisheries Bureau informs me that when he examined some years ago

the specimens of that form in order to determine its breeding season, he

remembers seeing two genital bundles, one on each side of the median

mesentery. There is therefore very little doubt in my own mind that

the form which SELENKA has signalized as Holothuria armata is the

northern form of Stichopus japonicus. It is easily distinguished by

having four rows of many long pointed papille along the two dorsal

ambulacra and the lateral margins, and by having numerous much small-

er papille interspersed between these four rows. ‘This form is found in

the Hokkaido (Yesso) and the northernmost part of the Honshu (the

main Island of Japan). As we go down southward in our country, the

42 K. MITSUKURI.

papille of Stichopus japonicus seem tod ecrease in number as well as

in height. This difference becomes so apparent when dried for the

market that dealers in dried “ namako ” divide them into those with spines

(papille) and those without them. The former is the northern form,

while the latter from the southern part, show only a row of low papille

along the lateral margins and few others scattered over the dorsal sur-

face. Those from Tokyo and the vicinity seem to be intermediate

between the two. I think that if the form found in the central part is

taken as the type of the species, the northern form with many papille

might be distinguished as var. armatus, while the southern form with

few papillae might be called var. australis. Of course, these pass into one

another insensibly. And even at one and the same locality, there seems

to be a great deal of difference in different individuals in this respect. I

. : am inclined to think that the habitat of the animal has a great deal to

do with the matter. Those that live among rocks along a rocky beach

seem to be distinguished by a larger number of tall papille as well as

by a mottled brown color, while those that live on sandy ground,

probably among sea-weeds, have lower and fewer papille and have

generally a dark green color. So that it seems possible to me to divide

the species into varieties by latitude and by habitat.

It would be a singular fact, if the changes in the shape of the calca-

reous deposits brought out above in Stichopus japonicus should turn out

tobe the solitary case of such an occurrence among the order of Holothu-

rioidea. I am rather inclined to think that if carefully studied, every

species will present more or less similar changes. If this should turn out

to be the case, I need hardly point out what an important bearing it has

on the systematic classification of the species of holothurioidea. At any

rate, those who collect holothurians should bear the fact in mind and

endeavor to obtain a large number of individuals in varios stages of

growth from different localities. )

Science College, Imp., Univ., Tokyo.

Printed May 16, 1897.

Revision of Hexactinellids with Disc-

octasters, with Descriptions

of Five New Species,

By Prof. I. Ijima, Ph. D.

Zoological Institute, Science College, Imp. Univ., Tokyo.

The discoctasters are, as enunciated by F. E. ScHULZE,* strongly

modified discohexasters in which the six principals have entirely or

almost entirely atrophied while the terminals have undergone a new

arrangement into eight secondary principals and terminal tufts at points

of the central node corresponding to the eight corners of a cube. This

peculiar kind of spicules have hitherto been known to occur in the follow-

ing four species of Rossellide, viz. Acanthascus cactus, F.E.S., Rhab-

docalyptus mollis, F. E. S., Rh. Roeperi, F, E. S. and Rh. Dowlingi,

L. M. Lambe. To this list, I will add five more species, making in all

nine discoctasterophorous species.

Before entering into diagnostic descriptions and systematic arrange-

ment of these species, I hold it essential to make, once for all, some

general notes on their structure.

They are all moderately thick-walled, barrel-like, cup-like, or vase-like

forms with a deep gastral cavity. Frequently the body shows lateral

compression after it has attained a certain size. The simple osculum is

situated at the upper end. The thin oscular margin is at first turned

inwards, but becomes later directed upwards or outwardly expanded.

Attachment to the substratum takes place by an irregular space at the

blind end, which region may be contracted in a stalk-like manner but is

never solid. When the sponge grows on an inclined or vertical sub-

stratum, it commonly happens that the basal region is bent so as to direct

the rest of the body upwards.

* Sitz-ber. d. kg]. Preuss. Akad. d. Wiss., XLVI, 1893.

44 Le NA

The power of opening secondary oscule or of budding out daughter

persons seems to be widely spread, although neither of them are ever

formed in any great number. A daughter person first arises as a

coecum-like outbulging of the wall, eventually to open an osculum at the

summit.

The principal parenchymalia are exclusively long diactins of well-

known nature and arrangement. The intermedia are always of three

kinds : discoctasters, oxyhexasters, and microdiscohexasters.

With respect to discoctasters, it is to be noted that the central

node contains a typical triaxial cross, which seems not to have been

observed before in this kind of hexactinellidan spicule. It is made plain-

ly visible when examined in glycerine or in any other medium of similar

refractive power. The six points of the cross are turned towards the

middle of the protuberant or otherwise somewhat concave space sur-

rounded by every four secondary principals. The terminals are always,

though often obsoletely, rough. The minute terminal dises are either

simply shaped like pin-head or toothed at the margin. It frequently

happens that deeply situated discoctasters are considerably larger than

those 1n the periphery.

The oxyhexasters, which are the most abundant of all parenchymal

intermedia, have very short and sometimes almost entirely atrophied

principals. The terminals are smooth or more frequently rough. The

roughness may develop at their basal parts into prickles with centrally

turned points. Not unfrequently the oxyhexasters situated near the

dermal surface differ from those more deeply situated in having longer

principals and more slender and more numerous terminals, although

they seem to be connected by transitional forms. ‘The most usual

number of terminals to a principal is two, and it very frequently happens

in such a bifurcated ray that one of the terminals is but very little deve-

loped or entirely absent. Thus I have seen cases in which a small rudi-

mentary and a normally developed terminal stood together on a princi-

pal. Then there are cases to be met with often enough, in which a

single terminal is joined to a principal by its crooked basal end. The

HEXACTINELLIDS WITH DISCOCTASTERS. 45

crook just mentioned is, in other cases, modified into a gentle bend and

in still others, completely straightened out so that now a principal and a

terminal jut out from the central node in a single straight ray. But

such a ray ought certainly not to be looked in the same light as the

primary undivided ray of a hexactin. The latter is invariably traversed

throughout its whole length by the axial canal, which, in the case of

hexasters, is likewise found in the principals but never extends into the

terminals. In conformity with the last mentioned fact, the apparently

simple and unforked hexaster rays already referred to, contain the axial

canal only at their bases, clearly demonstrating their constitution out of

a principal and of a single terminal. As is well known, one or more

rays in an oxyhexaster may be unforked or uniterminal ; and when all

are so and straight, as is of common occurrence, there arises a form

which is in shape a hexatin though not a genuine one in nature. Such

a spicule, when cleaned and examined in glycerine, will be found to con-

tain the usual central axial cross, the arms of which extend but for a

short distance into the bases of the six rays. ‘The impropriety of simply

calling it oxyhexactin, as has hitherto been the custom (SCHULZE, LAMBE,

RAUF), is evident. It should be called hexactin-shaped oxyhexaster.

The microdiscohexasters are probably never absent, although in

some species they occur quite sparingly. ‘They are of usual shape and

vary in diameter from 154 to 26.6.

The autodermalia are rough, straight diactins, stauractins, or pen-

tactins, one or the other of these predominating according to species.

Monactins, orthodiactins, and triactins are only of occasional occurrence.

As in all other Rossellids, a distally directed ray is never developed on

the autodermalia. When stauractins or pentactins constitute the main

elements, their cruciate rays are usually so arranged as to bring about

an autodermal lattice-work with more or less regularly quadrate meshes ;

whereas, in species with diactin autodermals, the meshes formed are

triangular, trapezoidal, or irregular in shape.

A hypodermal system of spicules is always present. For Acanthas-

cus cactus it is characteristic that the hypodermalia consist exclusively

46 1.’ KITIMA:

of diactins which are grouped in thin anastomosing strands. In the

rest of octasterophorous species, they consist of moderately large oxy-

pentactins, either solely or in union with subtangentially disposed

diactins. The proximally directed shafts of these hypodermal pentactins

are always smooth ; the four paratangential rays are also smooth or

minutely rough (Staurocalyptus), or else armed with biserially arranged,

strong, hook-like prongs (Rhabdocalyptus). The paratangentials are

often, though not always, paratropal, i.e. the four rays are, as it were,

pushed aside so that they form with one another three more or less acute

angles and one wide angle greater than 90° or even 180°. Similar hypo-

dermal pentactins have long been known in Rossella antarctica. As in

this species they are generally found in groups of several together. In

every such group, proximally directed shafts, accompanied with slender

comital diactins, form a more or less compact column or tuft that dips

deeply into the parenchymal mass, while the heads composed of paratan-

gential rays bring about a star-like figure, in which a number of streaks

radiate in all directions from what I will call, for the sake of convenience,

the hypodermal centre. It is easy to discover that the pentactin-heads

in a hypodermal group lie one above the other and that the one in an

upper situation is older and more fully developed than that following

next below. The lowest is therefore the youngest, which developes it-

self clasping with one of its angles the column of shafts belonging to

older pentactins. It is this preéxisting shaft-column that disturbs the

regularly cruciate development of the head of young pentactins; hence

the paratropal arrangement of paratangential rays.

The hypodermal pentactins remain in their locus nascendi only in

certain species. More usually they are destined to be protruded out-

wards through the autodermal layer as prostalia pleuralia. These stand

out isolated or in tufts from hypodermal centres; and, in case they are

not shed off, their paratangential rays form a gossamer-like veil at a

certain distance from the dermal surface, exactly as is known in the

genus Rossella.

Diactin prostalia are also of common occurrence. These are to be

HEXACTINELLIDS WITH DISCOCTASTERS. 47

considered as specially developed parenchymalia. In many species of

Rhabdocalyptus and Staurocalyptus I have found that in very young

individuals the needle-like diactin-prostalia project from all parts of the

body, but with growth of body, become restricted to the oscular margin,

where they may form an ill-defined, often interrupted fringe.

The autogastralia are as a rule rough hexactins with some excep-

tions. They may be represented by pentactins or by both pentactins

and stauractins. The autogastral pentactins has its unpaired ray al-

ways distally turned. In one noteworthy case (Staurocalyptus pleo-

rhaphides), the autogastrals are to be considered either as being not at

all developed or as being represented by short diactins that are not

sharply differentiated from parenchymal elements. When autogastralia

with cruciate paratangential rays are present in large numbers, they

form a continuous lattice-work with small quadrate meshes, covering

over the apertures of efferent canals. But when sparingly developed,

there are left in the autogastral layer wide gaps, by means of which the

efferent canals stand in direct communication with the gastral chamber.

Hypogastral strands are usually more or less distinctly present.

They are nothing else than certain strands of parenchymal diactins, that

have dissociated themselves in variable degrees from the parenchymal

mass and have entered into the support of the autogastral layer.

Finally with respect to dictyobasalia—by which name I designate

the thin reticular plate that invariably cover the surface of basal attach-

ment,—I believe that it is formed mainly by direct as well as synapticu-

lar fusion of special spicules developed by the stimulus of foreign bodies

in contact with the sponge. Where the plate is thin, the axial canal

contained in the nodes of beams has the shape of a simple cross, showing

that stauractins here lie as the structural basis. On the other hand,

where the plate is of certain thickness, the axial canals contained are

six-armed and even stout-rayed hexactins themselves are often discerni-

ble in the process of fusing with the dictyobasal beams,

The nine discoctasterophorous species, known to me at present, un-

doubtedly constitute a coherent group separated by a gap of not incon-

48 1.1: TIJIMA,

siderable extent from allied Rossellids in which the characteristie dis-

coctaster is represented by typical discohexasters. Probably the group

deserves to receive the rank of a sub-family, but I prefer to put off this

question until I have studied all my Rosselid materials. As will be seen

in the sequel I have distributed the species in question under three

genera. One of these, Acanthascus, although represented by a single

species, seems to me to be sufficiently distinct. With respect to the

rest, I must say that it would largely depend upon the individual caprice

of systematists whether to keep them on as two distinct genera, as I

have done, or to make only a subgeneric distinction between them.

GENus: ACANTHASCUS.

Discoctasterophorous Rossellids with exclusively

diactin hypodermalia.

This genus as originally established by F. E. ScHULZE in the Chal-

lenger Report, included besides the species given below, two more forms

that were called A. grossularia and A. dubius. These latter do not

possess discoctasters, which seem to be represented here by discohexas-

ters. On this account and from considerations of certain other points,

it seems to me justifiable to remove them altogether from the genus.

I think they might be included among Rossella more naturally than be

left in union with a discoctasterophorous species. Prof. SCHULZE him-

self has declared, in his letter to me, to share in this idea now. So then,

the genus Acanthascus remains with the following single species.

I. Acanthascus cactus, F. E. Sch.

Cup-like, vase-like, or fannel-shaped, often somewhat compressed,

with simple oscular edge ; dermal REST with conical elevations, bearing

on their apex a tuft of strong, needle-like, prostal oxydiactins. The

body may attain a large size of more than 450 mm. in height. It fre-

quently bears a limited number of secondary persons.

Parenchymal diactins small, probably never exceeding 15mm. in

length.

HEXACTINELLIDS WITH DISCOCTASTERS. 40

Discoctasters with 3-6 straight or almost straight, minutely rough

terminals on each principal. Length of entire rays (measured from

centre) 53-1304 ; those found in deep parts being often twice as large as

those lying near the dermal layer. In larger discoctasters the principals

are also rough-surfaced and the terminal discs 7-8 toothed.

Oxyhexasters 45-76 in radius, Principals exceedingly short or

almost entirely absent. Terminals rough, straight, stout; usually two

to each principal, but very frequently reduced to one, so that there

occur oxyhexasters with 11, 10, 9,8, 7 or even 6 points. In the last

case they may be typically hexactin-shaped though only in external

appearance. The principal is rarelv supplied with three terminals.

Microdiscohexasters of usual shape are of frequent occurrence es-

pecially in the dermal and gastral membranes.

Autodermalia are predominatingly rough stauractins forming a fine

lattice-work with quadrate meshes. This layer is supported by rather

thin strands of hypodermal diactins, forming a network of triangular,

trapezoidal, or irregular meshes, whose sides rarely exceed 2 mm. in

length.

Autogastralia are mainly rough pentactins. These do not form by

themselves a continuous autogastral lattice-work but are found scattered

on hypogastral strands together with discoctasters and oxyhexasters.

This species, known only from Sagami Sea, is one of the most

abundant Hexactinellids of that locality in depths of over 200 fathoms.

Genus RHABDOCALYPTUS.

Discoctasterophorous Rossellids with pentactin

hypodermalia, the paratangeutial rays of which are,

when fully developed, armed with biserially arranged

hook-like prongs.

When F. E. ScHULZE instituted this genus for the first time in

the Challenger Report, two species were described by him, viz. Rh.

mollis and Rh. Roeperi. Later Li. M. LAMBE* described a third species,

* 'l'rans. Roy. Soc. Canada. Sect. IV, 1893. p. 37.

50 1. IJIMA.

Rh. Dowlingi. Of these three species, only one, i. e. mollis, is retainable

in the present genus as defined above, while I will now add to it two

new species.

2. Rhabdocalyptus mollis, F. E. Sch.

Cup-like or vase-like, laterally compressed, contracted below, bear-

ing one or more tube-like secondary persons. The body may attain a

height of more than one foot.

Parenchymal diactins short, not exceeding 20 mm. in length. Disc-

octasters especially abundant in the subdermal region; ray-length

(measured from centre) 65-884 ; terminals 5-9 to a principal, rarely as

few as 2, straight or only slightly bent outwards ; terminal dise 7-8

toothed or simply pin-head like.

Oxyhexasters 51-80. in radius. Two varieties are distinguishable.

Those situated in deeper parts have usually two-forked rays, the princi-

pals being very short and often obsolete ; terminals smooth or minutely

rough, but always with more or less well developed basal barbs. Fre-

quently there is only one terminal to a principal, and hexactin-shaped

oxyhexasters are of common occurrence. Oxyhexasters found in the

subdermal region have longer principals and bear 2-4 usually 3 rough

terminals which are thinner and supplied with less prominent basal

barbs. Oxyhexasters with spirally twisted rays are not of constant

occurrence.

Microdiscohexasters of usual shape occur in variable numbers, es-

pecially in or near the dermal membrane.

Autodermalia are predominatingly rough diactins. Hypodermalia

consist of pentactins, pronged in fully developed state, and of smooth

diactins. The former have either paratropal or regularly cruciate heads,

and in places protected from external influence, may stand out isolated

as prostaha. Such a pentactin has paratangential rays not exceeding

5 mm. and a radial ray of not over 10 mm. in length.

Autogastralia are rough hexactins with bluntly conical ends, form-

HEXACTINELLIDS WITH DISCOCTASTERS. 51

ing a continuous lattice-work with quadrate meshes. The free proximal

rays do not differ in character from the rest.

Locality : Sagami Sea. I have myself collected some specimens

from depths of 274 fathoms and upward.

3. Rhabdocalyptus capillatus, n. sp.

Sac-like or vase-like, more or less strongly compressed. Oscular

edge fringed with thin needle-like prostals, not outwardly expanded.

Dermal surface thickly beset with pentactin prostalia which stand out in

tufts from every hypodermal centre and form a thick tolerably firm

gossamer-like layer all over the surface. The body may attain a height

of 210 mm.

Parenchymalia may contain bow-like diactins of 24 mm. in length.

Discoctasters are very small, measuring only 38-554 in radius, and are

of very characteristic shape. From a principal there arise 6-12 slender

terminals, which are always bent in an S-like manner and form a bunch

considerably expanded at the extremity. Terminal discs pin-head like.

Discoctasters are most numerously found in the gastral layer.

Oxyhexasters and microdiscohexasters as in Rh. mollis, but the

former have no or but little developed basal barbs. Hexactin-shaped

oxyhexasters are rare.

Autodermalia likewise as in foregoing species. Hypodermalia con-

sist solely of paratropal pentactins, which are grouped in closely con-

centrated centres. The older and pronged ones destined to be protruded

as pleural prostalia, have paratangential rays that may reach 12mm. in

length and a still longer shaft.

‘Autogastralia, forming a continuous quadrate mesh-work, consist of

rough hexactins with pointed ends, the free proximal ray being longer and

supplied with better developed microspines than all the rest of their rays.

Notwithstanding the close similarity of spicules, this species is easily

distinguishable from Rh. mollis by the smaller size and characteristic

shape of discoctasters, by the larger size and the persistence of pentac-

tin prostalia, etc.

52 I.:} (LJIMA;

Locality : Sagami Sea, from depths between 274 and 313 fathoms.

4. Rhabdocalyptus victor, n. sp.

Vase-like ; laterally compressed especially at basal part, which is

usually bent ; sometimes with one or two secondary persons on the

greater curvature of the basal region. Oscular edge simple or with an

interrupted fringe of thin diactin prostals. The body may attain a large

size, almost 3 feet high.

Parenchymalia may contain stout bow-shaped diactins, 28 mm. long

and 0.4 mm. broad at middle. Discoctasters 90-120 in radius ; termi-

nals 4-8 in a tuft, straight or slightly bent outwards; terminal discs

pin-head like.

Oxyhexasters 90-140 in radius. Principals exceedingly short or

obsolete, usually two-forked. Terminals rough, which character changes

towards base into small, inwardly directed prickles. Oxyhexasters with

two terminals to every principal occur less frequently than those in

which one or more principals bear only one terminal. Hexactin-shaped

oxyhexasters are of frequent occurrence.

Microdiscohexasters of usual shape and size are of very isolated

occurrence.

Autodermalia consist predominatingly of rough stauractins. Hypo-

dermalia as in foregoing species, but somewhat smaller (paratangential

rays 5-7mm. long). Unlike that species, the protruded hypodermal

pentactins seem to be readily thrown off, leaving at every hypodermal

centre a little bunch of the external ends of comital spicules, that accom-

panied the lost shafts, projected beyond the otherwise smooth surface.

In this respect, the present species agrees with Rh. mollis.

Autogastralia as in Rh. mollis.

Locality: Sagamı Sea, in depths sof over 274 fathoms. Next to

Acanthascus cactus, the present species is apparently the most abund-

ant octasterophorous Hexactinellid in the locality just mentioned.

HEXACTINELLIDS WITH DISCOCTASTERS. 53

GENUS STAUROCALYPTUS, n. gen.

Discoctasterophorous Rossellids with pentactin

hypodermalia, the paratangential rays of which never

possess hook-like prongs, but are either smooth or

minutely and uniformly rough.

To this new genus I should refer F. E. SchuLzE’s Rhabdocalyptus

Roeperi and L. M. LAMBE’S Rh. Dowlingi besides 3 new species to be

soon described.

5. Staurocalyptus Dowlingi (L. M. Lambe).

With some hesitation I consider certain specimens of Staurocalyp-

tus from Sagami Sea as identical with this species first described by

LAMBE (loc. cit.) from a specimen taken in the Strait of Georgia, Van-

couver Island, at a depth of about 40 fathoms. From Sagami Sea, I

have several, mostly fragmental specimens obtained at depths of over

235 fathoms. On these is based the following description.

Body subcylindrical or vase-like. It may grow to a considerable

size about a foot in diameter. Oscular edge turned upwards or in fully

developed state reflected outwards in flaps; simple and smooth or with

more or less needle-like prostals. External surface of smaller speci-

mens with a veil produced by the heads of prostal pentactins and

also with a number of long diactin prostals standing out in isolated

positions. After a certain stage of growth, both of these prostalia

pleuralia seem to be lost, except pentactin prostals in positions protected

from abrading influences. What constitutes one of the special charac-

ters of this species, is the spiny nature of the gastrai surface caused by

humerous needle-like (parenchymal) diactins that project their ends

beyond the gastral surface. In the specimens examined by LAMBE,

these gastral prostals seem to have been wanting.

Principal parenchymalia are bow-shaped and in large specimens

may measure 35mm. in length, but their dimension is, as in other

species, variable according to the size of individuals.

Discoctasters with radius of 72-1457 or more, those deeply situated

54 I. IIMA.

being generally much larger than and often almost or fully twice as

large as, those situated in the subdermal space. Terminals 2-8, usually

4-6, nearly straight, forming a slightly diverging tuft. Discs minute

and pin-head like or with toothed margin.

Oxyhexasters vary in radius from 38 to 80y according to indivi-

duals. When changed into hexactin-shape, the radius may measure as

much as 1107. Principals exceedingly short or obsolete. Terminals

2-3, more usually 2, and often only one to a principal, hexactin-shaped

oxyhexasters being of common or even abundant occurrence. Surface

of terminals either smooth or rough, in which latter case the roughness

may develop into small basal barbs. In some specimens only rough

bexasters are found ; in others both rough and smooth ones occur, and

then the latter are generally situated in deeper parts than the former.

Microdiscohexasters present in sparing numbers near the dermal or

gastral surface.

Autodermalia consist almost exclusively of rough pentactins with

rays 165, long and 8% broad in average.

Hypodermal pentactins comparatively small, usually not exceeding

4mm. in length of paratangential rays (sometimes larger). The latter

are either regularly cruciate or paratropal, according to their occurrence

in isolated position or in groups. Their surface is smooth, but when

fully developed, may become uniformly and thickly beset all over with

exceedingly minute protuberances, exactly as I have observed in

Staurocalyptus pleorhaphides, I}. or in Rossella longispina, Ij. Judged

from the series of specimens in my hand, it seems not improbable that

the power of giving the above mentioned roughness to the heads of

hypodermal pentactins is possessed by the present species only in young

state, losing that power after a certain stage of growth. So that the

oldest hypodermally situated pentactins as also all the prostal pentactins

may be rough-headed in small, but smooth-headed in large, individuals,

since in the latter all the rough-headed pentactins would have been shed

off during growth.

In forming the hypodermal strands, the paratangential rays of the

HEXACTINELLIDS WITH DISCOCTASTERS. 55

above-mentioned pentactins are supplemented by short smooth diactins

with or without annular swelling at centre.

Autogastralia are almost exclusively rough hexactins of approxi-

mately same dimensions as autodermalia. They are never present in

sufficient numbers as to form a continuous lattice-work. The gastral

layer therefore possesses gaps of small but variable size, bounded by

beams consisting of hypogastral diactins, intermedial rosettes and auto-

gastralia, similarly as in Acanthascus cactus.

6. Staurocalyptus Roeperi (F. E. Sch.)

This species is based on two specimens obtained by “ Challenger ” to

the south of Puerta Bueno in Patagonia. It is not represented in Saga-

mi Sea and is directly known to me only through two slide-preparations

kindly sent to me by Prof. ScHULZE.

The body should be sac-like or cup-like with sharp, smooth oscular

edge. The subdermal space, as seen through the even lattice-work of

the dermal membrane, should form irregularly scattered, elongated, an-

gular or spindle-shaped pits, whence arise rather narrow afferent canals.

On the inner surface round sharply contoured depressions of various

sizes occur, into the bottom of which the more or less wide efferent

canals open.

Spiculation closely similar to that of foregoing species ; but differing

in having much more slender rays to intermedial rosettes, dermalia and

gastralia ; in the sparing quantity of prickles on dermalia and gastralia ;

etc.

Discoctasters with radius of 65-83, without appreciable difference

in size according to position. Principals slender, not exceeding 4y in

breadth ; with 2-5 nearly straight, slightly diverging terminals with

minute, pin-head like discs.

Oxyhexasters very slender rayed ; 44—65y in radius, those near the

dermal surface being in general slightly smaller than those more deeply

situated. Principals short, often exceedingly short, bearing 2-3 straight

or wavy, obsoletely rough terminals. Cases of uniterminal principals

56 I. IJIMA.

present ; hexactin-shaped oxyhexasters probably not absent. It fre-

quently happens that in a dilophous ray, a third terminal is represented

by a spurious rudiment.

Microdiscohexasters of usual structure found in tolerable abundance

in the subgastral region.

Autodermalia are predominatingly pentactins, but stauractins are

by no means unfrequent. Occasionally triactins and diactins, rarely

monactins. Rays sparingly rough, not always quite straight ; 110-155,

long ; usually less than 5y in breadth at middle.

Hypodermal strands contain besides numerous slender diactins

with tuberculated centre, medium-sized pentactins whose slender rays

are smooth except at roughened ends. Head of pentactins not para-

tropal. It is not known whether these pentactins are ever extruded

beyond the external surface.

Autogastralia are oxyhexactins with sparingly rough rays of about the

same thickness as the autodermalia. Free proximal rays as long as 2307;

other rays somewhat shorter. According to SCHULZE, the autogastralia

line the gastral surface as also the surface of the wide efferent canals.

7. Staurocalyptus heteractinus, n. sp.

This species 1s founded on a single beau-sized specimen from Saga-

ini Sea. It represents a strongly compressed pouch with a small simple-

edged osculum on one side of the upper end. Texture as in other species ;

without prostalia pleuralia of any sort.

Discoctasters especially common near the gastral surface. Radius

55-100. Terminals 2-7 to a principal; straight, diverging. Disc

minute and pin-head like.

Oxyhexasters 53-57 in radius. Most of those situated in deeper

parts have two-forked rays with excessively short principals ; terminals

stout, straight, rough with minute prickles, which are more prominent

and inwardly turned near base. Peripherally situated oxyhexasters have

somwhat longer principals, each with 2-4, usually 3, rough-surfaced,

HEXACTINELLIDS WITH DISCOCTASTERS.

slender and straight terminals. Cases of a uniterminal principal have

not been met with.

Microdiscohexasters of usual structure found scattered in the

parenchyma.

Autodermalia consist mostly of faintly rough stauractins of variable

size, with occasional pentactins and triactins, rarely with diactins. Some

of these autodermalia are twice or even thrice as large as others. Ra-

dius 90-270; rays 9-137 thick near centre. Ends of rays rounded or

even clubbed. Autodermal meshes irregular, not rectangular.

Hypodermalia consist of irregularly distributed pentactins, with

occasional stauractins and triactins. Paratangential rays under !/, mm.

in length ; smooth, but often sparingly rough near the conically pointed

end ; not paratropal.

Autogastralia include faintly rough pentactins and stauractins, more

rarely triactins and diactins. Ray-length 55-100y; thickness near

centre 6.54 in average. They are not present in large numbers.

8. Staurocalyptus glaber, n. sp.

Goblet-like or vase-like ; laterally compressed ; thick-walled. Tex-

ture loose and light-looking. In young state with long diactin pleural

prostalia ; with age these become entirely lost or confined to oscular

margin. Prostal pentactins not found. The body may attain a height

of 250mm. Several specimens from Sagami Sea.

Principal parenchymalia more or less bent in bow-like manner ; not

over 13 mm. in length.

Discoctasters especially abundant in subgastral region; very large,

having radius of 250-330y, although smaller ones are not wanting.

Terminals 5-6 to each principal, nearly straight, slightly diverging ;

discs pin-head like.

Oxyhexasters 49-57 in radius. Principals short but usually dis-

tinct ; each with 2-4, usually 3, very slender terminals, which are faintly

rough near base.

58 I. IJIMA.

Microdiscohexasters occur not uncommonly in the dermal, less fre-

quently in the gastral, membrane. 6

Autodermalia are almost exclusively stauractins with rough or

prickly surface, the prickles on the external side being unusually well-

developed.

Hypodermalia consist of filamentous diactins and of moderately

sized pentactins with cruciate or paratropal heads. Paratangential rays

of the latter smooth but with rough ends. These are, I think, never

protruded beyond the dermal surface.

Autogastralia consist of comparatively large prickly hexactins, of

whose rays the free proximal ray is the longest (450-560). They form

a continuous lattice-work with quadrate meshes.

9. Staurocalyptus pleorhaphides, n. sp.

Thick-walled sac of abont the shape and size of a small pear. Oscu-

lar edge sharp and simple. The surface shows a number of low hillock-

like elevations from the apex of which long diactin prostalia stand out

in loose bunches. The body is moreover covered by a veil of pentactin

prostalia. Two specimens from Sagami Sea.

Principal parenchymalia, straight or bow-like ; not over 8 mm. in

length.

Discoctasters with rays 70-984 long; each principal with 2-4,

usually 3, diverging terminals, which are straight or slightly bent out-

wards. Discs minute, pin-head like.

Oxyhexasters with radius of 57, in average. Principals extremely

short; each with two, seldom more, rough-surfaced terminals. Fre-

quently one or more principals in an oxyhexaster are uniterminal, al-

though hexactin-shaped forms seem to occur but very rarely.

Microdiscohexasters present in sparing numbers.

Autodermalia are predominatingly rough diactins. Hypodermalia

consist of a few diactins and of numerous pentactins, whose heads are

either regularly cruciate or paratropal. Paratangential rays 5 mm. or

HEXACTINELLIDS WITH DISCOCTASTERS.

more in length ; smooth, but when fully developed, minutely and uni-

formly rough as in St. Dowlingi.

Gastralia are represented by diactins, some of which are similar to

autodermalia, while others are larger and very sparingly rough and

graduate over to parenchymal diactins.

More detailed descriptions with illustrations of all the above species

will be embodied in my monograph on the Hexactinellids of Sagami

Sea, which will be published in the Science College Journal.

Printed May 17, 1897.

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Miscellaneous Notes.

Ueber eine in Misaki vorkommende Art von Ephelota und über

ihre Sporenbildung, von C. Ishikawa. Journal of the College of

Science, Imperial University, Tokyo. Vol. X, Part II, 1896, S. 119-137.

Taf. XII-XIIT.—Diese in Misaki von mir in grosser Zahl auf dem

Sargassum beobachtete Art von Ephelota sieht, von den Seiten angesehen,

einem etwas plattgedrückten Hexagon gleich, und stimmt in vielen

Beziehungen mit der von R. HERTwIG zuerst entdeckten Ephelota

(Podophrya) gemmipara überein. Sie ist aber in vielen wichtigen

Puncten von dieser Art leicht zu unterscheiden, und zwar in dem Bau

des erwachsenen Thieres sowohl, wie in der Sporenbildung.

Bei dem Bau des Thieres kommen vor Allem die 'l'entakeln in Be-

tracht. Diese lassen sich in fünf Gruppen eintheilen, die von bestimmten

Körperregionen entspringen. 1) Eine Reihe von sehr langen Greiften-

takeln mit breiter Basis steht am oberen Rand des Körpers; 2) eine

zweite Reihe von Greiftentakeln, aber ohne die verbreiterte Basıs, an

dem mittleren Theil des Körpers ; 3) eine dritte Reihe von kleinen

Tentakeln am Basalende des Körpers um den Stiel ; 4) ein Kranz einer

Saugtentakelngruppe innerbalb der ersten Tentakelnreihe ; und 5)

kleinere vereinzelte Tentakeln zwischen den anderen. Von besonderem

Interesse dürfte die Thatsache gelten, dass in allen diesen Tentakeln

Fadenstrukturen zu beobachten sind, die mit Eisenhematoxylin sich

sehr stark und deutlich fürben lassen. Diese Tentakelstrukturen

bestehen in den beiden grossen Greiftentakeln aus vier parallel laufenden

Streifen, welche senkrecht zur Horizontalebene des Körpers stehen.

Jeder dieser vier Streifen ist wieder aus zweien zusammengesetzt.

Einige Aehnlichkeit besitzen diese Strukturen mit den neuerdings von

S. R. BeRGH in der Zellsubstanz zweier Infusorien, Spathidium

spatulae und Holophrya Emmae beobachteten “ Stutzfasern,” lassen

62 MISCELLANEOUS NOTES.

sich aber in beiden Fällen soweit von einander unterscheiden, dass

diese Fadenstrukturen in unserem Thierchen stark contractil sind, was

in den BERGH'schen Infusorien nicht der Fall ist.

Der grosse Nucleus, den ich mit BuùrscHLI als Macronucleus

anzunehmen geneigt bin, zeigt keine besonderen Eigenthümlichkeiten.

Er ist wie in Ephelota gemmipara stark verzweigt. Einige Micro-

nucleus-ähnliche Körperchen wurden nahe dem Mitielstück des Kernes

beobachtet, jedoch lasse ich die Natur derselben unbestimmt, da ich

keine T'heilungen dieser Körper warhgenommen habe.

Interessanter als der Bau des ausgebildeten Thieres, ist die

Sporenbildung. Bekanntlich producieren die europäischen Arten von

Ephelota freischwimmende Sporen auf der apicalen Fläche des Körpers.

Diese wurde auch in unserer Art beobachtet. Während aber die

europäischen bewimperten Sporen keine Tentakeln tragen, besitzen

unsere Sprösslinge gut ausgebildete Greif- und Saug-Tentakeln, selbst

wenn sie noch nicht von Mutterkürper losgelöst sind. Ws findet

sich in unserem Thierchen noch eine zweite Art von Sprösslingen,

welche die ganze Gestalt des erwachsenen Individiums annehmen, wenn

sie noch mit dem Mutterkörper zusammenhängen.

Die Zahl dieser Sprösslinge wechselt sehr (1-16), je nach der

Grösse des Mutterthiers. Es kann als Regel angenommen werden, dass.

ein grosseres ‘Thier mehr Sporen als ein kleineres besitzt.

Ueber die systematische Stellung des Thieres kann ich nicht be-

stimmt sagen. Allerdings besitzt die Art eine auffallende Aehnlichkeit

mit der europäischen Ephelota gemmipara. Ob man aber, nach den

oben angegebenen Merkmalen, unsere Art als eine neue anzusehen

darf, lasse ich noch unentschieden. Falls es aber so wäre, so möchte-

ich das interressante Thierchen zum Ehren des Herrn Professor Dr.

BÜTScHLt, “ Ephelota Bütchliana ” nennen.

C. ISHIKAWA.

Die Entwickelung der Gonophoren bei Physalia maxima, von

Seitaro Goto. Journal of the College of Science, Imp. Univ., Tokyo.

Vol. X, Pt. II, 1897, p. 176-191. With one Plate ——-This investigation

MISCELLANEOUS NOTES. 63

was carried on at the suggestion of Prof. Brooks in the Biological

Laboratory of the Johns Hopkins University, and was undertaken

primarily with the object of settling the question as to the nature of the

so-called female gonophores of HAECKEL, which are, however, regarded

by Brooks and CoNKLIN as swimming organs. The question is left

unsettled, as the writer has not observed any germ cells in these

structures. Considering their muscular nature it is very possible that

these organs have really a locomotory function, as claimed by Brooks

and Conkuin. If this is the case, then we know nothing yet about the

females of Physalia.

The so-called female gonophores are provided with a ring-canal and

four radial canals. The manubrium is present as a simple protuberance

of the ectoderm in the centre of the subumbrellar cavity. The bell-

nucleus is formed by the wandering in of interstitial cells from the

ectoderm.

Male gonophores were also studied, and the wandering of germ

cells observed. These take rise from the endoderm cells of the young

bud and wander out one by one into the subumbrellar ectoderm. The

germ cells have no distinct membrane, so that they appear imbedded in

a common mass of protoplasm. The cells of the subumbrellar ectoderm

are comparatively few and are, as in the so-called female gonophores,

the cells that have wandered in from the ectoderm, as described in a

preliminary note published elsewhere (Johns Hopkins Univ. Circulars,

no. 119).

The male gonophores have two radial canals when young; the

mature ones are, however, entirely destitute of them.

S. Goro.

On the Fate of the Blastopore, the Relations of the Primitive

Streak, and the Formation of the Posterior End of the Embryo in

Chelonia, together with Remarks on the Nature of Meroblastic Ova

in Vertebrates, by K. Mitsukuri. Contributions to the Embryology

of Reptilia, V. Jour. of the College of Science, Imp. Univ., Tokyo.

Vol. X, Pt. I, p. 1-118. Pl. I-XI.—In early stages of Reptilian embryos,

there is always an area free from the epiblast, directly behind the blas-

64 MISCELLANEOUS NOTES.

topore. When the latter becomes horse-shoe shaped, this area is enclosed

within it and becomes

Fig. 1. easily noticeable (fig.

2, A). Transverse and

longitudinal sections

through the spot in

question are as in fig. 1.

In Contrib. I, ISHIKAWA

and the author have

identified this epiblast-

free mass with the yolk-

plug of the Amphibian

ovum. The structure

has also been noted by

other writers, and its

theoretical significance

“has been interpreted in

Meso.

various ways. The

author, in the present

Contribution, follows

the fate of this “ yolk-

plug” stage by stage

in three species of

D. l'ransverse, section through the line AB, E. Longi- Chelonia Trionyzx

tudinal, section through the line X Y, in fig. 2A. _ he

F. Interpretation of the section E. Japonicus, Clemmys

Japonica, and Chelonia

CAOUANA.

When the medullary folds arise and reach the posterior portion of

the embryonic shield, they embrace the yolk-plug between their

posterior ends as in a vice, and compress it laterally, thus lifting it up to

the level of their dorsal surface. The yolk-plug meanwhile keeps its

own independence.

The yolk-plug now apparently recedes leaving in its track a groove

from which the cells are proliferated. This movement backward of the

yolk-plug is believed by the author to be caused by the active prolifera-

tion of cells from the lateral blastopore lips, while pressing to meet each

other in the median line. As cells thus proliferated accumulate, they

form a mass which necessarily pushes the yolk-plug backwards. This

pushing goes on, until the yolk-plug is placed at about the edge of the

MISCELLANEOUS NOTES. 65

embryonic area. The edges of the groove (or track left in the wake of

the yolk-plug) must therefore be considered the. lateral blastopore lips.

Fig. 2, A, B, C will make this clear. A is the stage in which the yolk-

plug has not yet begun its backward movement; in B it has moved

some distance, and in C it has reached its final position. In the last

stage, the blastopore therefore consists of three parts :—

Fig. 2.

ASTIQOSOHI

Dorsal opening

Swelling Neurent. Canal.

Y |

Er, fées /

a = /

eur

55 /

an” N %

se w ;

| ch

| 88

| AZ

k. Plug.

Diagrams showing three successive stages in the development of the posterior part of

the embryo.

(1) the dorsal opening of the neurenteric canal.

(2) the groove between (1) and (3).

(3) the groove around the yolk-plug in its final position.

66 MISCELLANEOUS NOTES.

The line of cell-proliferation from the blastopore lips of these

parts is the primitive streak. In Chelonia, and Clemmys, a groove

is distinct on the streak and represents the primitive groove ; in

Trionyx, it is absent, although sections show that cell-proliferation takes

place just the same.

The anterior half of the primitive streak is much thicker than the

posterior half and gives rise to the mass known as the “ Endwulst.”

The posterior half remains thin to the end. ‘The anterior thick part

rises as the tail-swelling. This is formed by the addition of the new

cell-mass on the dorsal surface, in other words, by upheaval or elevation

and not by folding,

When the tail has arisen to some height, the primitive streak and

groove should of necessity be found over the dorsal median line of the

tail, around its tip to the ventral median line, and then be continued to

the thinner part of the primitive streak outside the embryo proper, until

they reach the yolk-plug. They are thus &-shaped. Such a condition

is actually seen in Chelonia up to quite a late stage. In Clemmys, the

anterior part of the streak and groove over the tail disappears rather

early. In Trionyx, the groove does not exist from the first, and the

streak also disappears early from the tail part.

In the tail which lengthens itself backwards, the medullary chord,

the notochord, the enteron, and the mesoblast are differentiated in situ

in the tissue surrounded by the epiblast.

The primitive streak finally disappears entirely by the separation of

the layers, with the exception of a short stretch on the ventral surface

of the tail. The proctodæum is formed at this point.

The yolk-plug, at the latest stage observed, stands out as an append-

age of the epiblast. Probably it persists to a late stage as a rudimentary

useless structure. In Clemmys, it is elongated posteriorly and forms on

the floor of the posterior amniotic tube a prominent ridge, the signi-

ficance of which is not clear.

In Theoretical Considerations, the developmental processes as

above described are compared in detail with those brought out by

SCHWARZ, SEDGWICK, the ZIEGLERS and others in Elasmobranchii and

the identity of the so-called yolk-plug in Chelonia with the large yolk-mass

of Elasmobranchii is maintained. The conclusion is reached: “the

course of events described in the preceding pages as taking place in the

posterior portion of the embryonic area resulting in the formation of the

posterior part of the embryo in Chelona is a repetition, in a rudimentary

MISCELLANECUS NOTES. 67

form, of the process affecting the homologous parts in Elasmobranchii ”

(p. 88).

Also “ It seems most reasonable to conclude that in course of phy-

logenetic development, the yolk which is homologous with the yolk-mass

of the Elasmobranch egg must have dwindled in size and been lost

from the eggs of the ancestors of the Amniota. This yolk-mass which

I may call the primary yolk-mass has, however, left in some eggs (e. g.

in the Chelonian egg) its rudiments in the structure known as the primi-

tive plate and its direct derivative, the problematical cell mass* behind

the blastopore. In further course of development, the eggs of the

ancestors of the Amniota acquired for the second time a large yolk-mass

which I may call the secondary yolk-mass. It is this which we see in

the Amniota eggs of the present day. * * x Thus it becomes im-

perative to distinguish the meroblastic egg of the Elasmobranchii from

the meroblastic egg of the Amniota. "The former may be called the

primary meroblastic ovum or proto-meroblastic ovum and the latter the

secondary meroblastic ovum or meta-meroblastic ovum” (p. 90).

Comparisons are also briefly made with the processes seen in Am-

phibia, Aves and Mammalia.

Finally, the classification of the vertebrate eggs is made as follows :—

I, Primary TYPE. (a) Archi-Holoblastic (Amphioxus), (b) Proto-

Holoblastic (Cyclostomi), (c) Proto-meroblastic (Elasmobranchii, Teleostei)

(d) Meso-holoblostic (Amphibia ?).

II. SECONDARY Type. (a) Meta-meroblastic (Reptilia, Aves), (b)

Meta-Holoblastic (Mammalia).

In a postscript, WILL's article ‘ Die Anlage der Keimblätter bei

der Eidechse (Lacerta) “ Zool. Jahrb. Abth. f. Anat. IX. Bd. is reviewed.

K. MITSUKURI.

A Living Specimen of Plevrotomaria Beyrichii.——By the kind-

ness of Alan Owston, Esq. of Yokohama we were favored, on the 31st of

March last (1897), with a view of a living individual of tbat rare mollusk,

Pleurotomaria Beyrichit. The specimen had been received by him, the

day before, and had probably been caught by a long-line at the Okinose

Bank off Boshù. The animal was not very lively and could not be

persuaded to extend itself fully. At the utmost, we were able to see the

foot and a part of the head. The sole of the foot was straw-yellow.

The side of the foot and the throat were mottled with large and small

* Le. the “ yolk-plue.”

68 MISCELLANEOUS NOTES.

patches and streaks of deep carmine-red on the ground color of reddish-

yellow. The proboscis was uniformly deep carmine-red. The left

tentacle had a small branch near the tip. On the sides and the posterior

aspect of the foot, we were able to make out two lobes, one standing up

from each side of the foot and applied to the shell. It seemed probable

to me that when fully extended, these lobes etiveloped the shell to a

greater or less extent—a supposition which is strengthened, as was

first pointed out by Mr. NAMIYE, by the fact that the shells of Pleu-

rotomaria, hitherto found, are all extremely clean and have never

barnacles, worm-tubes etc. attached to them. The mantle was not at all

visible and we were thus not able to see how it is related to the slit on

the outer lip. As this is, so far as we know, the first time, a living

specimen of Pleurotomaria has come into the hands of a naturalist, it

has been thought worth while to put the fact on record.

K. MIPSURKURI.

The Ophiurian Shoal.——In the course of a collecting tour which

we made last spring (1896) in the provinces of Satsuma and Osumi

(in Kiushiu), we met with a curious mode of occurrence of an ophiurian

which is perhaps worth noting here. On the eastern side of the island

Sakurajima in the Bay of Kagoshima, there is a small village called

Kurokami. A few hundred metres off the sea-front of this place there is

a small sandy shoal named Hamashima which becomes exposed at low

tide. ‘Towards the evening of April I, after having skirted the island

the whole day, we found ourselves approaching this shallow. As our

dug-out boat struck the bottom, all of us eagerly waded into water

which was at the time fifteen to twenty centimeters deep. We were

soon struck with very curious objects. | Numerous slender stalks a few

millimeters in diameter and 10-15 centimeters high were standing up

from the bottom, looking, for all we knew, like the stems of so many

weeds. Along one side of each stalk, there was, however, a row of

Fig. 3. white papilla-like structures. These stalks

were mostly by twos, although sometimes

\ f only one was standing by itself. We do not

a: remember having seen three making a group.

As we dug to learn more about these curious

objects, we were greatly surprised to find that

they were the arms of ophinrians, and that

the papilla-like structures were therefore no doubt tube-feet. So far as

we could see, there was no difference between the five arms of the

MISCELLANEOUS NOTES. 69

animal and why only one or two of them should be thus thrust upwards

into the water, and kept upright there, was a mystery. It seemed

probable to us that it was done to secure respiration. he sand of the

shoal was literally packed with these animals, and there must have been

hundreds of thousands or perhaps millions in the whole shallow. We

did not hesitate to give the spot the zoological sobriquet of the

“ Ophiurian Shoal.” These ophiurians were of a species belonging to

the Amphiuride and near or in the genus Ophiopsila. Together

with them we found a species of Synapta in tolerable abundance and

one individual of Sipunculus.

K. Mrrsuxurt and T. Hara.

Zoological Society of Tokyo——The monthly meeting of the

Society for January was held at 2 P.M. on Saturday, Jan. 23, in the

lecture room of the Zoological Institute of the Science College. Prof.

MITSUKURI in the chair. The following papers were read :

Mr. S. YosHrwARA on “Two Japanese Species of Asthenosoma.”

The substance of this paper is found elsewhere in the present part of

this periodical.

Mr. H. WATANABE on “ the Phosphorescence of Cypridina Hilgen-

dorfit, Müller.” The conclusions arrived at by the author were as

follows :

(1) The phosphorescent ostracod known in Misaki as ‘ marine

fire-fly ” is Cypridina Hilgendorfii, Muller.

(2) The phosphorescent organ of this ostracod is a group of elongat-

ed, unicellular, epidermal glands opening to the exterior symmetrically

on either side of the median line, on the external edge of the upper lip

—the glands called by Claus “ Oberlippendrüse ” in 1873.

(3) The glands secrete, together with the transparent, colorless

“secretive vacuoles,” yellow homogeneous granules which are stored

in the necks of the glands.

(4) Physical as well as chemical stimuli cause contraction of the

muscles of the upper lip, and the secretion of the glands is thereby

mechanically squeezed out.

(5) The phosphorescence of Cypridina Hilgendorfü is a chemical

phenomenon accompanying the contact of pigment of the granules with

the external medium, i.e. sea water.

(6) The presence of free oxygen in any considerable quantity is

70 2 MISCELLANEOUS NOTES.

not essential to the manifestation of phosphorescence ; on the contrary

the presence of water, unless it be strongly acid, is a sine qua non of the

phenomenon. :

(7) As the phosphorescent organs of the metazoa seem to be

generally derived from a glandular transformation of the ectoderm, so

physiologically they are attributable to a pigment producing change in

the glands ; the phosphorescence being simply a collateral phenomenon

due to contact of a yellowish pigment, capable of. changing into red or

green, with water. It is,-generally speaking, a means of frightening

other animals, possessed by certain aquatic organisms or those living

in a moist medium. :

Prof. MITSUKURI exhibited some specimens of Peripatus sent him

from the University Museum of Cambridge, England.

The meeting adjourned at 4.30 P.M.

The monthly meeting of the Society for February was held at the

usual place at 2 P.M. on Saturday, Feb. 20. The President in the

chair. The following papers were read :

Prof. MITSUKURI on “the Changes accompanying Growth in the

Calcareous Bodies of Stichopus japonicus, Selenka.” The substance of

this paper is found elsewhere in this periodical.

Dr. KIsHINOUYE on the “ Petasma and Thelycum of some Shrimps.”

The author dwelt at length on the morphology and physiology of these

structures in several species. The substance of the paper is promised

in a near future in the pages of this periodical.

The meeting adjourned at 4 P.M.

The monthly meeting of the Society for March was held at the

usual place at 2 P.M. on Saturday, March 2. The President in the

chair. The first part of the meeting was taken up by business concern-

ing the issue of a new periodical in European languages. The following

papers were then read :

Mr. H. Kurorwa on “the Zoology of the Ryukyu Islands.”

The author gave an interesting, detailed account of his experiences as

a collector in these islands, referring specially to the habits of the

gigantic bat and the dugong.

Mr. H. WATANABE on “ Plankton and Tidal Currents.” The author

dwelt on a close correlation of the quantity of plankton and tidal cur-

rents, as shown in his table of quantitative plankton studies made in

Misaki. He also exhibited some specimens of the plankton.

MISCELLANEOUS NOTES. 71

Mr. IxkebA exhibited a specimen of an octopod of the genus

Amphitretus, recently obtained of a Misaki fisherman,

The meeting adjourned at 5 P.M.

List of Japanese Zoologists. ——As some changes have taken

place among our zoologists since the publication of FRIEDLANDER’s

Adressbuch, we believe the following list with adresses will be welcome

to our foreign confrères.

Zoological Institute, Science College, Imp. Univ., Tokyo.

| Mitsukuri, Kakichi, Ph. D., Rigakuhakushi. Director, and Professor of Zoology in the

College. Specialty— Embr. Vert., Syst. Holoth.

-Jjima, Isao, Dr. Phil., Rigakushi, Rigakuhakushi. Professor of Zoology in the College.

Spec.—Plathel., Aves, Spong. a

Namiye, Motoyoshi. Assistant. Spec.—Syst. Vert.

suchida, 'l'oshîzo. T'axidermist.

Nagahara, Kotaro. Draughtsman.

J'akakura, Usamaro, Rigakushi. Grad. Stud. Spee.—Nemert.

Hara, Jüta, Rigakushi. Grad. Stud. Spee.—Myzostomum, Crin.

- Omori, Senzö, Rigakushi. Grad. Stud. Spec.—Actin.

- Aida, Tatsuo. Grad. Stud. Spec.—Chaetogn:

- Yoshiwara, Shigeyasu. Grad. Stud. Spee.—Echin.

- Watanabe, Hisakichi. Grad. Stud. Spee.—Planktol., Trachomed.

Tizuka, Akira. Grad. Stud. Spee.—Polych.

- Nishikawa, ‘l'okichi. Grad. Stud. Spee.—Embr. Pisces.

-Kdoyama, ‘l'orata. Grid. Stud. Spec.—Oligoch.

‘Terazaki, l'omekichi. Special Student. Spec.—Hmbr. Aves.

“Miyajima, Mikinosuke. Spee.—Myriap.

- Ikeda, Sakujito. Spec.—Cephalop., Amphib.

Shishido, Ichiro, Rigakushi. Spec.—Syst. Pisces.

Zoological Institute, Agricultural College, Imp. Univ., Tokyo.

- Ishikawa, Chiyomatsu, Dr. Phil., Rigakushi, Rigakuhakushi. Director, and Professor

of Zoology in the College. Spec.—Cyt., Arthrop.

» Sasaki, Chujiro, Rigukushi, Rigakuhakushi. Professor of Zoology in the College.

Spee.—Insecta.

Tsuchida, Toshiwo. ‘l'axidermist.

Anatomical Institute, Medical College, Imp. Univ., Tokyo.

- Koganei, Ryosei, Dr. Med., Igakuhakushi. Professor of Anatomy in the College.

Osawa, Gakutaro, Igakushi. Now in Freiburg i. Br, Germany.

Higher Normal School, Tokyo.

‘ Iwakawa. l'omotaro, Rigakushi. Professor of Zoology.

Frist High School, Tokyo.

* Goto, Seitaro, Rigakushi, Rigakuhtkushi. Professor of Biology. Spec.—Plathel., Embr.

Echin.

72 MISCELLANEOUS NOTES.

Nobles’ School, Tokyo.

- Hatta, Saburo. Professor of Biology. Spec.—Embr. Cyclost.

Fisheries Commisson, Tokyo.

- Kishinouye, Kamakichi, Itigakushi, Rigakuhakushi. Spee.—Embr. Artlurop., Medus.

Kitahara, Tasaku. Spec.—Ichth.

Otaki, Keinosuke. Spee.—Ichth.

School of Fisheries, Tokyo.

- Matsubara, Shinnosuke. Spec.—Syst. Pisces.

- Fujita, Tsunenobu, Rigakushi. Spec.— Moll.

Rakusuien, Mayebashi.

- Inaba, Masamaru, Rigakushi, Spec.—Hydromed.

Yamaguchi High School, Yamaguchi.

> Oka, Asajiro, Dr. Phil., Rigakuhakushi. Professor of Biology. Spee.—-Tun., Polyz., Hirud.

Yasue, Toyotaro. Instructor of Zoology.

Fifth High School, Kumamoto.

Nakagawa, Hisatomo. Professor of Biology.

Agricultural School, Fukushima.

- l'oyama, Kametaro, Nogakushi. Principal of the School. Spec.—Spermatog.

Fisheries Department, Sapporo, Hokkaido.

Nozawa, Shunjiro, Nögakushi. Spec. Insec., Syst. Pisces.

Agricultural College, Sapporo, Hokkaido.

- Matsumura, Matsutoshi, Nögakushi. Spec.—Entom.

Minami, Takajiro, Nögakushi. Spec.— Entom.

Yushukwan, Fukuoka.

Matsui, Katsunori, Rigakushi.

Gitu.

Nawa, Yasushi. Spec.—Entom.

Hihikosan, Fukuoka.

‘l'akachiho, Norimaro. Spec.—Æntom.

Normal School, Naha, Ryukyu.

Kuroiwa, Hisashi. Professor of Biology.

PRINTED AT THE “ T'oxyo PRINTING Co., Lp.” ‘l'orto, JAPAN.

i =

ero

: hee ten ES e

ZOOLOGICAL SECTION.

E have always on hand for Scientific purposes and Ornaments of the

household, well prepared Skeletons and good stuffed Skins of Mam-

mals, Birds, Reptiles and Fishes: Birds’ Eggs and Nests: Shells

and Insects.

Also we prepare Specimens in Spirit of Land and Marine

Animals.

All our Specimens are collected by exp2riencad Collectors and mounted

by Skillful Taxidermists.

We collect any kind ot Animals immediatly on order.

We have also for sale Instruments and Reagents for Zoological

studies and Taxidermists’ and Collectors’ use.

We have the honor of being favored with orders from the Imperial

Museum, the Department of Commerce anl Agriculture, the Im-

perial University, Middle and Normal Schools, both private and

government.

Specimens are sent on prepayment of price.

Payments are to be directed to YONHKICHI KOMEYAMA,

Proprietor.

DOBUTSU-HYOHONSHA,

NO. 1, GOKENCHO, KANDA, TOKYO,

JAPAN.

CONTENTS.

Pear-horer (Nephopteryx rubrizonella, Rag.).....................,.....1 M. Matsumura.........

On Two New Species of Asthenosoma from the Sea of Sagami...S. Yoshiwara. .........

Chaetognaths of Misaki Harbor..." "#28... DEE ARE

On the Accommodation of Some Infusoria to the Solutions of

Certain Substances in Various Concentrations. ..........,..........2 AE din. er

On Changes which are found with Advancing Age in the Calcare-

ous Deposits of Stichopus japonicus, Selenka......................... K. Mitsukuri......

Revision of Hexactinellids with Discoctasters, with Descriptions

of. Five. New. Species. .... sauer. 00.0.0 ee Deere eee AMONG 2.00

Miscellaneous Notes. tate ae RITIENE TIT eee see eee

wane

Ueber eine in Misaki vorkommende Art von Ephelota und über ihre Sporenbillung, von C. ISHIKAWA.—

Die Entwickelung der Gonophoren bei Physalia maxima, von S. Go10.—On the Fate of the Blastopore,

the Relations of the Primitive Streak, and the Formation of the Posterior End of the Embryo in

Chelonia, together with Remarks on the Nature of Meroblastie Ova in Vertebrates, by K. MITSUKURI.

— Living Specimen of Plenrotomaria Beyrichii.—The Ophiuran Shoal.—Zoological Society of Tokyo.—

List of Japanese Zoologists

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ANNOTATIONES

ZOOLOGICÆ JAPONENSES

AUSPICIIS

SOCIETATIS ZOOLOGICÆ TOKYONENSIS

SERIATIM EDITA.

Volumen I Pars Lif.

TOME

PUBLISHED AUGUST 10, 1897.

NOTICE.

The “ Annotationes Zoologicæ Japonenses ” are published quarterly,

in January, April, July, and October.

Terms of subscription—$ 1" =4s= F5 = M4 per annum; single parts

25¢=Is=F1.25=M1]1 each. Postage included in all cases.

Remittances from foreign countries are to be made by postal money

orders, payable in Tokyo to M. Namiye, Zoological Institute, Imp. Univ.,

Tokyo.

TO CONTRIBUTORS.

Articles may be written in English, German, French, or Italian.

Each contributor receives 50 copies of the reprints of his article

gratis. Any number of extra copies will be furnished at cost.

Contributors are particularly requested to specify the number of

reprints they want at the end of the manuscript. If not specified 50

copies will be delivered.

Articles may be accompanied by simple illustrations, as far as pos-

sible in lines and dots.

Communications are to be addressed to the Secretary of the Zoologic-

al Society of Tokyo, Zoological Institute, Imp. Univ., Tokyo.

OCT 1 1397

On a Mode of the Passage of the

Eye in a Flat-Fish.

By T. Nishikawa.

Zoological Institute, Imp. Univ., Tokyo.

On a very quiet and brilliant morning of Aug. 10th. of last year,

a transparent young flat-fish was caught with a surface-net at the

mouth of the harbor of Misaki. The fish was then swimming vertical-

ly ; but when placed in a glass vessel, it turned on its right side and

remained motionless on the bottom for hours. It was 1.3 cm. in

length and about 0.4 cm. in height. It had no pigment, and was quite

transparent. The mouth was asymmetrical, a single nostril was pre-

sent on the left side, and the vertical fins were confluent, while the

pectorals were not to be seen. The two eyes were then situated symme-

trically with reference to the longitudinal axis of the body. Fig. 1 re-

presents the profile of the anterior part of this flat-fish, as drawn on the

morning of that day. It will be seen that the dorsal fin has already

extended itself along the head to the anterior extremity of the snout, but

this extended part of the dorsal had as yet no fin rays, only the soft

tissues having grown forwards. What is remarkable is that this

anterior extension, although applied

closely to the head, has not coalesced

with it, and that at the inner base of

the anterior extension, there was @

clear large hole passing from one

side to the other. he posterior bor-

der of the hole was about on a level

with that of the eyes.

As the animal was watched, the

right eye gradually travelled, with

74 T, NISHIKAWA.

the rotation of the head, towards the dorsal side of it, and approached

more and more the base of the dorsal fin ; eventually it passed into the

hole between the head and the anterior extension of the dorsal.

This stage is shown in fig. 2, which

was drawn at 10 : 30 P.M. of the same

day; the anterior extension of the

dorsal fin has not yet united with the

head. The right eye then emerged

on the left side and moved towards

its final position. After this rota-

tion, there occurred a fusion of the

head and the anterior part of the dor-

Fig. 2. sal fin, from the base towards the

snout. Thus it was evident that the hole in front of the base of the

dorsal was intended for the passage of the right eye, which travelled

around the dorsal surface of the head, from the right to the left side.

There occurred neither a new formation of the orbit for the right eye on

the left side nor the atrophy of the original orbit of the right eye on the

right side, as in the case of the Plagusia described by AGASSIZ.*

The fish died on the evening of the next day, after the rotation of

the right eye was finished; it had then many pigment-spots on the left

side, and the snout was produced backwards into a hook, covering the

mandible. The general characters of the young fish being still very

incomplete, it was not possible to identify it, but it is probable that it

belongs near the genus Plagusia.

According to the observations of AGaAssrz, there are two different :

modes of the passage of the eye in flat-fishes ; one of them is undergone

by a majority of species, such as Plewronectes, Pseudorhombus, and

others. In this mode, the eye on the side which in the adult is blind,

travels round the dorsal side of the head, till it attains its final position,

* A. Acassız.—On the Young Stages of some Osseous Fishes. II. Development of

the Flounders. Proc. of the Amer. Acad. Arts & Sci., vol. XIV. 1878.

SIT

PASSAGE OF EYE IN FLAT-FISH.

and only after this votation, the dorsal fin grows forwards beyond the

level of the eyes. In the second mode which is undergone by Plagusia,

the dorsal fin grows forwards to the snout, while the eyes are still in

their initial positions. When the right eye in the course of rotation.

approaches the base of the dorsal fin, it gradually sinks into the tissues of

the base of the dorsal fin, between it and the frontal ; so that the right eye

is now not to be seen on the surface ofeither side. A very interesting

circumstance was observed by Acassız, that a fresh orbital opening is

formed for the right eye on the left side, and that the original orbit of

the right atrophies after the rotation of the eye; therefore in a certain

stage of metaniorphosis, there are three orbital openings: one on the

left side, the original orbit of the left eye; a small one on the left side,

the new orbit for the right eye ; and a small orbit on the right side, the

remnant of the original orbit of the right eye. He says, “ With the

continued sinking of the right eye, the gradual resorption of the tissues,

and the closing up of the old orbit, as the eye works its way across the

head, we eventually get the right eye entirely over to the left side. It

has now, by a movement of translation and of rotation, penetrated

through the tissues between the base of the dorsal fin and the frontal

bone ; having apparently passed through the head, as was suggested to

STEENSTRUP, by his examination of the alcoholic specimens which

furnished him the materials for his paper on Plaqusia.”

In the present flat-fish, the dorsal fin also grows forward before the

rotation of the right eye, but this anterior extension does not unite

with the head, and there is a distinct hole bounded by the head and the

anterior extension of the dorsal fin, for the passsge of the right eye,

which travels round the dorsal side of the head without sinking into its

tissues. ‘The orbit of the right eye travels also with the rotation of the

head from one side to the other, as in the case of a number of flat-

fishes: Now if we compare this mode of the passage of the eye with

the first mode described by AGASSIZ, which is undergone by a majority

of flat-fishes, we find little difference between them, beyond the fact

that before the rotation of the eye takes place, the dorsal fin grows in

78 m. WATDA.

show that the cells which constitute the stalk-—or stalk-cells as I shall

call them hereafter—are produced from the cells of the germinal epithe-

lium by a succession of amitotic divisions and fuse one after another

with the ovum until the latter becomes mature.

We thus find two or three stalk-cells at the base of a young ovum.

Fig. l is a cross section of the ovary of Sagitta bipunctata hardened

with Flemming’s stronger solution. Each of the ova « and d has two

stalk-cells at its base, where the germinal epithelium makes a deep inden-

tation. «isa nearly mature ovum and its cytoplasm shows a fine

cobweb structure. It has at its base a large stalk-cell which appears

as a stopper to the spaceous indentation of the germinal epithelium

under the ovum, and an indication of another cell which has been ab-

sorbed by the ovum. dis a younger ovum and its cytoplasm is a dense

reticular mass. ‘There is a distinct stalk-cell which has been taken up

by the ovum, and below it there is another which serves as the stopper

to the indentation in the germinal epithelium. This last cell is smaller

than the stopper cell of the ovum a, as.is also the indentation of the ger-

minal epithelium under it compared with the corresponding structure

under the ovum a.

In order to show that these stalk-cells are produced from the ger-

minal epithelium by amitotie division a few of the nuclei undergoing

that process have been sketched, and are reproduced in fig. 2. We find in

the germinal epithelium two kinds of nuclei ; those belonging to the first

kind have each a looped varicose chromatic filament (fig. 2, b lower

nucleus) and he generally in the deeper portion of the epithelium ; the

nuclei belonging to the second kind, which are found in the external

portion of the germinal epithelium (fig. 2, a, b, upper nuclei, €, d.), have

many dispersed chromatic particles and a central body of aggregated

chromatic substance containing in its center a nucleolus-like structure,

which can be well differentiated from the peripheral chromatic portion

by a double-staining with orange G and hematoxylin. The second

kind of nuclei is produced by direct division from the first class: a part

of the long looped chromatic filament is first constricted off as a round

OVARIAN OVUM OF CHAETOGNATHS. 79

mass constituting the central body of the second kind, and;the part

which follows it disintegrates into granules and are dispersed within

the nucleoplasm. In fig. 2 d, the central body has already separated off

from the looped chromatic filament, and the outer part of it, which is

within the daughter nucleus, is disintegrating into granules.

By a succession of such direct division, several nuclei with a central

body are produced within a cell of the germinal epithelium from a

nucleus with the looped chromatic filament (a and e fig. 2, fig. 3).

Each of these nuclei then separates with a little protoplasm, as a stalk-

cell one after another, and is at last merged into the ovum, the merging

beginning from that which is nearest to the ovum. In the ovum 4, fig.

1, and a, fig. 5, the upper stalk-cell is fusing with the ovum and in c,

fig. ] and fig. 3, we see half disintegrating nuclei as remains of the fused

stalk-cells. But the nucleus with the looped chromatic filament goes

on dividing and producing daughter nuclei indefinitely. After a certain

number of division, it is converted wholly into a nucleus with the

central body. Two lower nuclei of a, fig. 2, are in their last division.

The chromatic filament being stretched equally into two nuclei after

the completion of division, two similar nuclei with the central body will

be produced. The central body is, in this case, produced from the

central part of the equally divided chromatic mass, the outer part of it

being disintegrated into the granules.

The nucleus with the central body may also divide amitotically.

The separation of the central body is followed by the constriction of the

nucleus in a manner similar to the amitotic division of nucleolated nu-

clei as described by various authors (d, e, fig. 2).

Besides these amitotic division which results in the formation of

equal sized daughter nuclei, the nucleus of both kinds may divide un-

equally in size and produce one or more small fragments (0, ¢, fig. 2).

It is not rare to find a number of these fragments at the base of a nu-

cleus with the looped chromatic filament.

Thus the nuclei of the cells in the germinal epithelium multiply by

direct division and separate as stalk-cells. These are one after another

80 l. AIDA.

absorbed into the ovum to which they are attached, until the latter has fully

grown. Often we see these cells arranged under an ovum like a stair,

fig. 5, as Grasst found in the young ovum of some species (Sagitta

Claparedi). I was unable to find a stalk cell with such a long tail-like

portion as Grasst describes; all the stalk cells of our specimens of

Sagitta bipunctata, Sagitta enflata, Sagitta serratodentata, etc. are

round or rectangular.

The ova, which have no follicle, must take their nutriment from, or

through, these stalk-cells. Lam inclined to believe that the stalk-cells

do not merely serve as food materials to the ova, but that they in some

manner perform the function of actively nourishing the ova, as a follicle or

a nutritive cell does, and that when they lose their capacity for that fune-

tion are merged into the ovum at whose base they lie, andare replaced by

the next cell. When all the stalk cells derived from a single epithelial cell

are taken up, others will be produced from a neighboring cell to nourish

the same ovum to its maturation. Thus as the cells of the germinal

epithelium are constantly taken up by an ovum, there is necessarily formed

an interruption in the epithelium directly under the ovum, and this inter-

ruption becomes the wider, the greater the number of cells taken up.

The last one of the stalk-cells, which is attached to the ripe

ovum, is always larger than its predecessors and behaves somewhat dif-

ferently from them. It is never fused with the ovum to which it is

attached, but remains as a stopper of the interruption in the germinal

epithelium (a, fig. 1». Itis this stalk-cell which Conanv* has described as

preceding the ovum in its passage to the temporarily formed oviduct. I

must notice here that the deepness of the interruption varies according

to the thickness of the germinal epithelium. In animals which have

a thin germinal epithelium, e. g. small specimens of Sagitta bipunctata,

Sagitta enflata, Sagitta minima, ete., it is so shallow that the enlarged

stalk-cell nearly fills it up, and is easily overlooked.

From certain stages in its development, an ovum shows at its

* Ann. & Mag. N. at Hist. ser. 6, vol. 18, no. 105, 1896

OVARIAN OVUM OF CHAETOGNATHS. 81

periphery many globules of various size, which may be called yolk-

nuclei (the black dots in the ova of fig. 1). They show similar reac-

tions to coloring matters as the inner part of the central body or the

nucleolus of the stalk-cell nucleus. Probably they are derived from

the latter, which persists after the fusion of the stalk-cells and changes its

peripheral chromatic substance to a refractive amorphous mass similar

to its inner part, and is metamorphosed into small globules which by

reunion produce larger ones.

As to the question whether the ovum passes outside through the

ovisperm duct or through a temporarily formed passage as CONANT in-

sists, I am unable to give an opinion, as none of my specimens had ova

‚in this stage.

In conclusion I may remark once more that ın the germinal

epithelium of chaetognaths, there are two kinds of nuclear division,

mitotic and amitotic ; and that the ova are produced by mitotic, and the

stalk or nutritive cells by amitotic, division. This fact seems to lend

support to the hypothesis of ZIEGLER and Vom Ratu on the fate of

the cells produced in these two different ways.

Printed July 20, 1897.

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ANNOT. ZooL. JAP., Vou. I. IAB AVE

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Notes on the Paludina-Species of

Japan.

By T. Iwakawa.

Professor of Zoology, Higher Normal School, Tokyo.

With PI. V.

While engaged in reärranging the shell collection of the Imperial

Museum at Uyeno, Tokyo, I have found among it a pretty extensive

series of native Paludina specimens from localities ranging from Awomori

at the north-eastern extremity of Hondo as far south-west as the island

of Shikoku. Advantage was taken of this opportunity to make a sys-

tematic study of the genus, but as I soon felt the desirability of having

more materials in order to arrive at satisfactory results, and especially

as the labelling of localities appeared in some cases unreliable, I

have given special attention to obtaining fresh paludinas while on a

collecting tour in the northern provinces during the summer of 1896.

On that occasion, I enjoyed the agreeable company and valuable

assistance of Prof. C. IsuiKawa and also the coöperation of Messrs. K.

Matsuura and I. HoRIKAWA, assistants to the Zoological Department of

the Imperial Museum. Two hundred and eighteen fresh specimens were

brought home from different localities, chiefly in the provinces of Mutsu,

Rikuchu, Rikuzen, and Iwashiro. These, added to the old specimens

of the Museum, formed a material of over five-hundred, which number

further received considerable augmentation through the kind gifts of

several friends in different parts of the country. For specimens from

middle Japan I am especially indebted to Mr. M. Kawarsura of Kami-

suwa, Prov. Shinano, and to Mr. Y. NawA of Gifu. Mr. Kurorwa of

the Normal School of Naha has kindly sent me specimens from Yaye-

yama Shima, Loo-choo Islands. To all the gentlemen above named I

wish here to tender my thanks.

84. È TT. IWAKAWA.

In Dr. W. Kose t’s well-known work “ Fauna Japonica extra-

marina ” (1879), are given the following eight species :

1. Paludina japonica, v. Martens. Hab. Tokyo, Yokohama, Hakone

Lake.

2. Paludina Sclateri (v. Frauenfeld. Hab. Biwa Lake.

3. Paludina stelmaphora (Bourgnignat). Hab. Tokyo, Yokohama,

Biwa Lake, Yawatahama.

4. Paludina oxytropis, Benson. Locality not specially mentioned.

5. Paludina ingallsiana, Reeve. Hab. Biwa Lake.

6. Paludina nitens, Reeve. Hab. “Japan.”

7. Paludina abbreviata, Reeve. Hab. “ Japan.”

8. Paludina laeta,v. Martens. Hab. “ Japan.”

Of the three last-mentioned species, viz. nitens, abbreviata, and

laeta, there exist but very meagre diagnoses ahd no figures. It seems

these species were never found again since they were first described.

Indeed, there are not wanting in my collection certain specimens which

somewhat approach the diagnosis of one or the other of them, but I

found anything like satisfactory identification impossible. More speci-

mens from the south-western provinces, which are still in need of thorough

exploration, might possibly throw light on the validity or non-validity

of the three species in question; but, considering the great variability of

other well-established species, it is exceedingly doubtful if any of them

would ever be found tenable as distinct species.

On the other hand, the remaining five species or forms given by

KoBELT are represented in my collection, although they can not all be

held up as specifically distinct. In fact, I can recognize in my material

only three species, viz. stelmaphora, ingallsiana, and oxytropis.

Pal. stelmaphora and Pal. ingallsiana present no difficulty in

being regarded as good species. Whereas, Pal. japonica, Pal. Sclateri

and Pal. oxytropis has seemed to me rather doubtful as to their specific

distinctness from the outset, since they were often found mixed together in

one and the same locality. A thorough study of my specimens revealed

the fact that both japonica and Sclateri insensibly grade over to o@ytropis,

NOTES ON THE PALUDINA-SPECIES OF JAPAN. 85

and must therefore be looked upon as varieties of the latter.

In identification I have found it of great importance to bring into

consideration the form of young shells in different stages of growth,

either found free or taken from within the body of mother shells.

For, the young have characteristic shape for each species and are very

persistent in their characters in comparison with adults.

I. Paludina stelmaphora (Bourgnignat).

Pi. V, figs. 1-4.

The specimens which I refer to this species, have characters essen-

tially agreeing with the original diagnosis of BOURGNIGNAT and with the

description given by KoBELT (loc. cit.. p. 122). The principal characters

are as follows :

Shell swollen, egg-shaped, thin, smooth, with a greenish epidermis,

umbilicated. Spire low, with an obtuse apex usually worn out in old

specimens. Whorls quite rounded, separated by deep sutures; each

whorl wound round with three punctured lines, which, though some-

times extremely fine, are always present and easily visible to the naked

eye. In young individuals the lines are often beset with fine hairs.

These punctured or haired lines seem to be peculiar to this species ; they

are not found in any other Japanese species of Paludina,in which we find

raised lines instead. They were described by KoBELv but were omitted

in his figures. Aperture nearly round, obtusely angled at the upper end.

Edge of outer lip turned out, consisting of a thin epidermis which is

connected with the inner lip by a thin callosity, margined with a black

band. In fully grown specimens, the surface of the body-whorl is

provided, especially close to the outer lip, with some elevated ribs

besides the several lines of growth. Interior of the aperture bluish-

colored. Height 43—58 mm. Diameter 26—36 mm. Aperture 22—

30 mm. long, 19—23 mm. wide.

Specimens of this species very often present hammered-like sculp-

ture on the surface (P. malliata, Reeve). As was correctly re-

cognized by KoBELT, these should not however be made into a distinct

86 T.'° IWAKAWA.

species, since they are counected by intermediate forms with those that

are devoid of the sculpture. A collection of stelmaphora from one and

the same locality may show an abundance of transitional forms from

smooth-surfaced individuals to others that have a distinct hammered-like

surface. Moreover this character of the shell is not peculiar to stelma-

phora, being also met with in some individuals of orytropis.

The embryo-shell (fig. 1) of this species is amber-colored and

extremely delicate, consisting of only three or four whorls with a very

low spire. Hach whorl is perfectly rounded at the shoulder except on

the body-whorl which is somewhat angular along the middle and is

besides provided with exceedingly fine spiral lines. The aperture is

generally rounded above, while its basal portion at the lower end of the

columella is stretched out so as to form a short canal. As the shell

grows, the angle on the body-whorl generally disappears and the three

punctured lines characteristic of this species are developed (fig. 2—4).

I have specimens of P. stelmaphora from Awomori in Prov. Mutsu,

Kogawara Swamp in Prov. Rikuchu, Miyagi in Prov. Rikuzen, Fuku-

shima in Prov. Iwashiro, Kasumigaura in Prov. Hitachi, Tokyo, Aichi

in Prov. Owari, Tokushima in Prov. Awa, and Yayeyama Shima. Thus

it will be seen that the present species has a very wide distribution in

Japan, from Tsugaru Strait as far south as the Loo-choo Islands. At the

latter locality, this seems to be the only species of Paludina present,

according to a private communication of Mr. Kurorwa.

Further it may be noted that this species is confined to shallow

water broadly exposed to light, such as rice-fields. So far as my obser-

vation goes, it never occurs in such places as lakes or rivers where

water is deep and cold.

2. Paludina ingallsiana, Reeve.

Pl. V, figs. 5—7.

This is an exceedingly variable species, the several forms of which

are well represented and described in KoBELT’s monograph. Notwith-

NOTES ON THE PALUDINA-SPECIES OF JAPAN. 87

standing its variability, the species is easily distinguishable by the fol-

lowing characters :

Shell pyramidal or turret-shaped, with apex sometimes extensively

worn out in mature specimens. Sutures deeply canal-like, owing to

the abruptly outstanding edges of whorls, between which edges

the whorl-surface is flat or even slightly concave. In some speci-

mens, each whorl is provided with two or three distinct, spiral

raised lines; in others there is only one such line on the body-whorl,

bringing about an angle at the outer lip. The surface is either rough

and incrusted with a reddish substance or perfectly smooth and vividly

green. Height 43—51 mm. Diameter 23—30 mm. Aperture 18—25

mm. long, 14—19 mm. wide.

Fig. 5 represents one of the youngest specimens of ingallsiana from

Lake Suwa. It will be seen that its shape is quite different from that

of the corresponding stage of either stelmaphora (fig. 3) or oxytropis

(fig. 9).

This excellent species has hitherto been known only from Lake

Biwa, to which I will now add two more localities,. Lake Suwa in

Prov. Shinano, and Nagoya in Prov. Owari, on the strength of the

specimens contained in the Imperial Museum.

In Lake Biwa, it seems to be very common. Mr. K. MATSUURA

incidentally obtained there several specimens, while collecting fresh-

water fishes together with Prof. C. IsHIKAWA during the summer of

1895.

From Lake Suwa there was originally only one specimen of this

species in the Museum. Recently Mr. M. Kawarsura of that locality

has made a collection at my request and kindly sent me a number of

fresh specimens.

With respect to specimens from the Province of Owari, of which

there are three in the Museum, the exact locality is unknown.

In the north-eastern provinces of Hondo, I could not obtain a

single specimen of this species, in spite of my efforts to collect during

the excursion of last summer. It is very desirable to ascertain its range

88 T. IWAKAWA.

of distribution in Middle Japan and also in the south-western provinces,

where it probably also occurs.

3. Paludina orytropis, Benson.

After disposing of the two species above noticed, the rest of my

specimens offered some difficulties in being identified. While some of

these were referable to oxytropis (after KoBELT), others to FRAUENFELD’S

species Sclateri and still others to v. MARTENS’ japonica, there were many

with intermediate characters. After all I have come to the conclusion that

japonica and Sclateri must be regarded merely as varieties of orytropis.

Typical Pal. oxytropis (fig. 12) has the shape of a double cone. Spire

usually acutely pointed, consisting of 6 or 7 whorls ; shell thiv and trans-

lucent, upper whorls only slightly swollen or nearly flat, separated by

narrow and shallow sutures ; each whorl provided with three or four dis-

tinct raised lines, of which the lowest runs at the sutural line, while the re-

maining lines run so as to divide the whori-surface into a corresponding

number of zones, usually nearly equal, but sometimes unequal in width.

The middle portion of the body-whorl forms a distinct angular ridge,

below which there are numerous spiral lines converging towards the

umbilicus. Aperture oval but more or less acutely angular above and

below ; peristome thin and sharp, its portion at the lower end of

columella alone being a little turned out; all the extremities of raised

lines form more or less acute angles at the margin of outer lip.

Pal. oxytropis var. japonica (fig. 17) (=Pal. japonica, v. Mart.)

differs from typical orytropis in the following characters : shell ovoid-

conical, moderately thick and opaque, usually with somewhat obtusely

pointed spire; whorls swollen, separated by wide and deep sutures ;

raised lines indistinct or absent except one on the body-whorl, where

it makes a very slightangular ridge. Aperture nearly round, with an

obtuse angle only at the upper end, and with thick peristome, which is

considerably expanded ontwards and downwards.

NOTES ON THE PALUDINA-SPECIES OF JAPAN. 89

Pal. oxytropis var. Sclateri (fig. 14) (= Pal. Sclateri v. Fr.) is dis-

tinguished from the typical form by having oval, thicker and heavier

shell, with an obtuse apex; whorls swollen, but not so much as in the

above variety, and separated by very shallow sutures. Raised lines

persist in each whorl, though not so prominent as to give rise to angles

at the peristomal margin. Aperture oval, with obtuse angles above and

below ; edge of peristome very thick, and the outer lip slightly expanded

outwards.

Notwithstanding the differences of adults, the young of the typical

form and of its varieties all agree in characters. The embryo-shell

(fig. 8) is light green and consists of five whorls, with a conical pointed

spire. Three raised lines are distinctly to be seen. The last of these

lines brings about a conspicuous angle at the margin of the outer lip,

the aperture showing four angles in all. The general shape of the shell

is that of a double cone.

The main features of embryonal characters above referred to are

retained during the growth of the shell (figs. 8—11), to be directly con-

tinued further on into the adult stage in the case of typical orytropis,

but to deviate at a certain period of growth into the respective definitive

characters of japonica and Sclateri, where these are concerned. This is

the ground on which I base my conclusion that orytropis represents the

primitive stock, whence japonica and Sclateri have differentiated.

I will here let follow an account of the specimens collected by myself

at different localities in the north-eastern provinces to illustrate how

this species varies.

1) Most of the specimens from a muddy stream in Yamagata village

near Lake Inawashiro, Prov. Iwashiro, distinctly show the characters

of typical oxytropis. Fig. 12 was drawn from one of the specimens

collected at that place. In four out of fourteen specimens obtained, the

spiral raised lines were either indistinct or nearly absent while the

whorls were more or less swollen, which characters made them approach

either japonica or Sclateri. In the majority of specimens the three

90 T. -LWAKAWA.

raised lines were prominent ; in some there were one or sometimes two

more lines interposed between the first and the second, and in still

others another raised line was added above the first. The angular edge

of the body-whorl was very prominent in all Yamagata specimens.

The largest individual of the lot measured 70 mm. in height and

55 mm. in diameter, with an aperture 39 mm. long and 29 mm. broad.

2) In the specimens from Shinai Swamp in Prov, Rikuzen, eighteen

in all, both typical orytropis and var. japonica are represented. Eight

are referable to the former and the rest to the latter. In all and even in

old specimens the apex is uninjured and the shell perfectly smooth, and

vividly green in color. The typical orytropis specimens, although of

normal configuration in young stages, have somewhat lower raised lines

than those of Yamagata. This seems to indicate that Shinai specimens

have a greater tendency to change into japonica form.

3) The specimens from a small swamp near the village of Nagahama

on the northern shore of Lake Inawashiro are all var. Sclateri in both

the shape and thickness of the shell, but they still retain the character

of typical oxytropis in so far as the prominent raised lines are present.

The embryo-shells have typical oxytropis shape.

4) In specimens from a canal near the village Shariki, Prov.

Mutsu, the definitive characters of var. Sclateri are settled, although the

embryo-shells are typical oxytropis as ever.

5) The specimens from Hirobuchi Swamp, Prov. Rikuzen, show

abundance of transitional forms, typical oxytropis into var. Sclateri,

while the tendency to change into var. japonica is indicated only in a

slight degree. In all cases, embryo-shells have the shape of the typical

species.

6) Finally, the specimens collected at Kogawara Swamp, Prov.

Rikuchu, are of great interest in that they serve for definitely settling

the question as to the mutual relationship of the three forms. ‘The

young have invariably the shape and characters of typical oxytropis

(figs. 8—11). Among the adults the Sclateri form prevails. There are

besides unmistakable japonica form and others that combine the charac-

NOTES ON THE PALUDINA-SPECIES OF JAPAN. 91

ters of the typical orytropis with those of either Sclatert or japonica.

Adults with the characters of typical orytropis are not found in this lot.

In fig. 14 I have represented a specimen from this locality, which

must certainly be considered as Sclateri. In its general shape, the form

of the aperture and the nature of raised lines, it tallies well with the

description and figures given by KoBELT of that form.

Fig. 17 represents a specimen from the same locality, which is a

true japonica characterized by outbulged whorls, by the expanded outer

lip of the aperture and by the partial absence of raised lines, The

young specimen drawn in fig. 9 was taken from this individual.

As examples of varieties with combined characters, I have given

Late of three specimens in figs. 13, 15, and 16. Both the specimens

of figs. 13 and 16 have almost the shape of Sclateri, but at the same time

approach oxytropis in the character of raised lines, which is especially

the case with the specimen of fig. 13.

The individual of fig. 15 is nearly orytropis in its general shape, but

the raised lines have all disappeared except one on the body-whorl,

which respect it is like japonica.

I wish to emphasize once more that the young of all the varieties

above mentioned are essentially oxytropis in character, so that figs. 8—11

might pass as young stages of any one of them. Here is, I think,

a sufficient ground to conclude that Pal. orytropis represents the ances-

tral species whence the several varieties have arisen.

Tpagawa, LOUE UN det; Te

(4: 4 in “a

| sinh

‘lode

€

EXPLANATION OF FIGURES.

'l'hree young stages of Pul. stelmaphora from Shariki, Prov. Mutsu. — reinpi fa

An adult form of ditto. % DAI

Two young stages of Pal. ingaUsiana from Suwa Lake, PARRA!

An adult form of ditto. Tr it paci car pone

Four young stages of Pal. 0 opis from Kogawara Swam Rikuchn. | DI

Pal. oxytropis, a typical forn ‘rom Yamagata, Prov. Iwashi vali

Two intermediate forms between oxytropis and Selateri fro

Pal oxytropis var. Sclateri from ditto.

An intermediate form between ( oxytropis and japonica from dito.

Pal. oxytropis var. japonica from ditto.

Leti

TRA

}

pui

ANNOT. ZooL. JAP., Vou. I.

pe e)

T. Iwakawa. del,

Dendrocoryne, Inaba, Vertreterinn einer

neuen Familie der Hydromedusen,

Von Seïtaro Goto.

Zoologisches Laboratorium der Ersten Hochschule in Tokio.

Hierzu Taf. VI.

Als ich im vorigen Herbst eine Umordnung meines Laboratoriums

unternahm wurde ich einiger Exemplare der Hydromedusen gewahr,

die mir so merkwürdig erschienen, dass ich sie bei Seite stellte, um

sie nachher einer näheren Untersuchung zu unterziehen. Auf weiterem

Studium der Literatur fand ich dass diese Hydromedusen schon vor

einigen Jahren und zwar 1892 von meinem Freund Herrn MASAMARU

INABA beschrieben worden sind. Da seine Beschreibung aber japanisch

geschrieben in unserer „:Zoological Magazine “ verborgen bleibt, so

möchte ich mit Bewilligung des Verfassers eine Uebersetzung derselben

mit den Originalfiguren voll anführen, und dann einige eigene Beobach-

tungen mitteilen.

„36*. Gen.? sp.? (Figg. 106-110.)

„Lrophosom—Der Tierstock erreicht in der Höhe 10 cm. oder

mehr, Verzweigung unregelmässig, die Zweige sind aber mehr weniger in

einer Ebene angeordnet. Das Chitin bildet nicht eine oberflächliche

Schicht sondern ein Innenskelett von feinem netzförmigem Gerüst. Die

dünnere Zweige stellen im Querschnitt einen Kreis dar. Die Polypen

kommen zerstreut vor und wachsen unmittelbar aus dem Stamm her-

vor, ohne besonderen Stiel, spindelförmig. Tentakeln kugelförmig

verdickt an der Spitze, 16-20 zerstreut an der Körperoberfläche,

* Diese sowie die folgende Nummer bezieht sich auf die Reihenfolge der aufgezähl-

ten Arten in der Originalarbeit, deren ‘Vitel folgendermassen lautet ? Sösha Miura Misaki

Kinbò ni oite etaru Hydroidea (Die in Misaki, Minra, Sdsha, und seiner Nachbarschaft

gesammelten Hydroiden), und welche in Bd. 4 (No. 41) der „Zoologienl Magazine,“ Tokyo,

veröffenlicht worden ist.

94 sh (GONO)

108.

106. Ein kleiner Teil des Tierstocks von Dendrocoryne misakinensis. Nat. Grosse.

107. Derselbe etwa. 8 mal vergrössert. Es gibt drei Gonophoren.

108. Querschnitt eines diinnen Zweiges ; nur der chitinöse Teil ist wiedergegeben. Zeiss

2 aa.

109. Spitze eines dünnen Zweiges: nur ein einziger Polyp ist eingezeichnet ; man sieht

das chitinöse Netzwerk an der Oberfläche des Zweiges. Zeiss 2 AA.

110. Längsschnitt eines weiblichen Gonophors. Zeiss 2 CC:

DENDROCORYNE. 95

„Gonophor-—Medasoide, nie freischwimmend, mit einem kurzen

Stiel aus dem Stamm hervorwachsend ; linglich ellipsoidisch, 2 mm. lang.

Das Ostium ist nicht deutlich, seine Stelle jedoch ist durch vier rundliche

Kôrper bezeichnet. Das Manubrium nimmt den ganzen Innenraum

der Umbrella fur sich in Anspruch. Das Obige bezieht sich nur auf das

weibliche Gonophor ; das männliche ist noch nicht bekannt.

„Farbe—Chitinöser Netzteil braun, Polypen und Gonophoren

farblos.

„Fundort— Westlich von Misaki, auf den Steinen wachsend, aus

der Tiefe von etwa 6-7 Metern.

„Datum—Januar 1889.

,, Diese sonderbare Hydroide wurde bisher mehrmals gesehen worden,

aber man hat sie als eine Art von Actinozoen angesehen. Als ich aber

dieselbe näher zu betrachten kam fand ich zu meinem Erstaunen dass

sie eine wahre Hydroide ist. In den Werken von ALLMAN, HINCKS u. a.

habe ich eine der vorliegenden Art etwa nahe stehende Form nicht ausfin-

dich machen können. Meines Erachtens stellt sie vielleicht eine neue Art

von einer neuen Gattung dar. In Misaki aber kommt eine zweite,

naheverwandte Art vor ;ich werde zunächst auf deren Beschreibung über-

gehen und dann einige allgemeine Bemerkungen über beide vorlegen.

„31. Gen.? sp.? (Figg. 111-113.)

„Lrophosom—Der Stock erreicht im der Flöhe 10 cm. oder mehr,

Verzweigung unregelmässig, die Zweige sind aber sämtlich in einer

Ebene angeordnet. Das Chitin bildet ein Innenskelett von feinem

netzförmigem Gerüst. Die Zweige sind meistens plattgedrückt, und auf

ihrer Oberfläche kommen der Länge nach verlaufende vorspringende

Rippen und stumpfe dolchformige Fortsätze vor. Die dünneren Zweige

stellen im Querschnitt ein plattgedücktes Viereck dar. Von der Nähe

der dolehförmigen Fortsätzen springen nach der Seite hin Polypen her-

vor ; sie sind mehr weniger cylindrisch, schlank, und besitzen zerstreut

an ihrer Oberfläche an der Spitze kugelformig verdickte Tentakeln,

die in Zahl 20 nicht übersteigen, und von denen 4 oder 5 einen Ring um

den Mund bilden.

96 Ei GOTTO:

111. Ein Teil des Tierstocks von Dendrosoryne secunda. Die Polypen sind von einem

! YI

Teil weggelassen. Nat. Grösse,

112. Derselbe ; es gibt männliche Gonophoren. Zeiss 2 AA.

113. Querschnitt eines dünnen Zweiges ; nur der Chitinteil ist wiedergegeben ; ein Polyp

ist in seiner natürlichen Lage eingezeichnet. Zeiss 2 AA.

„Gonopnor—Medusoide, nie freischwimmend, wachsen meistens aus

den Axillen der Polypen hervor, mit einem kurzen Stiel versehen, kugel-

rund, die vier Radialkanäle deutlich ; die an deren Gipfel befindlichen

vier randlichen Körper sind auch deutlich und treten aus der Oberfläche

hervor ; das Ostium kommt niemals zur Ausbildung ; das Manubrium

nimmt den ganzen Innenraum der Umbrella in Anspruch. Das Obige

bezieht sich nur auf das männliche Gonophor ; das weibliche ist noch

nicht bekannt.

„Farbe—Chitinteil braun ; Polypen farblos.

DENDROCORYNE. 97

„Fundort— Westlich von Misaki, auf den Steinen wachsend, aus der

"Tiefe von 6-7 Metern.

, Datum—Juli 1889.

„Ich hegte den Zweifel ob diese und die vorhergehende nicht ein

und dieselbe Art bildeten, aber nach näherer Beobachtung wurde ich

davon gewahr dass es nicht so ist. Die Fortpflanzungszeit fur die

erstere ist als Januar angegeben, aber nach dem mir vorliegenden Exem-

plar zu urteilen ist die Fortpflanzungstitigkeit zu dieser Zeit schon

etwas abgewachsen, die Zeit der regsten Fortpflanzung ist also wahr-

scheinlich October bis November. Für die zweite Art ist die Fortpflan-

zungszeit dagegen Juli. Andere Unterschiede zwischen den beiden Arten

kommen in der Verzweigungsweise des Tierstocks, in der Form der

Polypen, im Bau des Chitingerüstes und in der Form der Gonophoren

zum Ausdruck.

„Das Gonophor-der ersteren Art ist ellipsoidisch, das der zweiten

kugelrand ; auch die Radialkanäle sind bei den beiden nicht gleich

deutlich ; da aber bei der einen Art nur das weibliche Gonophor mir

vorliegt, bei der anderen dagegen nur das miinnliche so ist seine Form-

verschiedenteit wohl auf die des Gesehlechtes zurückzuführen. Der

Polyp ist spindelförmig bei der einen, eylindrisch bei der anderen. Die

Verzweigungsweise des Tierstocks ist sehr verschieden ; bei den beiden

ist die Verzweigung unregelmässig, aber bei ber zweiten Art sind die

Zweige in einer Ebene angeordnet, so dass die Verschiedenheit der

beiden Arten in dieser Beziehung sogleich bemerkbar ist.

„Zuletzt will ich den Chitingerüst besprechen. Derselbe besteht aus

Fäden, von denen die longitudinalen resp. die transversalen einander

nahezu parallel verlaufen. In den Maschen liegt der weiche Gewebe.

Das Chitinskelett ist überall vorhanden, so dass es seine Bigengestalt

nicht verlieren würde, selbst wenn man den weichen Gewebe entfernen

sollte. Ueber die Anordnung der beiden Korperschichteu kann ich nichts

mitteilen. Meiner Meinung nach gibt es zu äusserst eine lüktoderm-

schicht wie bei Podocoryne und Hydractinia, wie man teils in Fig. 109

ersehen kann. Die Maschen sind bei den beiden Arten grob im Achsen-

98 Si- NGOTO:

teil, und klein nach der Peripherie ; bei der ersteren sind dieselben rund-

lich, wie in Fig. 108, bei der letzteren aber sind sie vieleckig (Fig. 113)

und senden an der Peripherie dornformige Vorspringe aus.

„Fassen wir nun also den beiden Arten gemeine Charaktere zusam-

men: Der Stamm besitzt ein Chitinskelett, ist dendritisch verzweigt,

sendet nach unten kriechende Wurzeln aus, mittelst welcher er am

Substrat festsitzt ; der sitzende Polyp ist mehr weniger spindelförmig,

und besitzt zerstreut an seiner Oberfliche am Ende kugelförmig

verdickte Tentakeln. Das Gonophor ist eine nie freischwimmende

Medusoide, und besitzt vier Radıalkanäle.

„Ich schlage für diese neue Gattung den Namen Dendrocoryne vor,

und nenne die erstere Art (No. 36) D. misakinensis, die zweite (No. 37)

D. secunda. Diese Gattung ist durch den Bau der Polypen und

des Gonophors der Syncoryne am nächsten verwandt, aber das Chitin-

skelett scheint ähnlich wie bei Podocoryne angeordnet. Bei dieser bildet

das Chitin eine dünne oberflächliche Schicht, bei der neuen Gattung aber

ist es baumförmig ; die Weise wie der Polyp von demselben vorspringt

ist bei den beiden dieselbe. Bei Podocoryne ist das Chitinskelett

röhrenförmig, bei Dendrocoryne dagegen ist dasselbe stäbchenförmig,

was man nicht leicht vorübergehen darf.“

Im in No. 42 der ,, Zoological Magazine “ erschienenen Teil der

obigen Arbeit fasst INABA die Gattungsdiagnose folgendermassen zu-

sammen!

„ Lrophosow— Der Stamm ist verzweigt, besitzt ein inneres Chitinskelett,

unten verbreitet, erhebt sich von fadenförmigen kriechenden Stolonen ;

Polypen sitzend, spindelförmig, und tragen zerstreut an ihrer Oberfläche

am Ende kugelförmig veidickte Tentakeln. Gonophor—Medusoide,

Umbrella tief, Radialkanäle vier, Randtentakeln vier, rudımentär.“

Durch die Güte meines ehemaligen Lehrers, Herrn Prof. Dr. Mrrsu-

KURT wurde ich in den Stand gesetzt die von INABA gesammelten und im

Museum des Zoologischen Instituts der Kaiserlichen Universität depo-

nirten Exemplare zu untersuchen, und da INABA aus äusseren Gründen

sich sehr wenig der Schnittmethode hat bedienen zu können scheint,

Ne)

Das

DENDROCORYNE.

so glaube ich seine Berchreibung verbessern und einige Lucken darin

ausfüllen zu können.

Was zunächst die äussere Gestalt des Tierstocks betrifft, so ist

schon von INABA hervorgehoben worden, dass bei Dendrocoryne secunda

alle Zweige in einer Ebene angeordnet sind. Dagegen scheint die Ver-

zweigung bei D. misakinenszs etwas unregelmässig : bei den im Univer-

sitätsinuseum befindlichen Spiritusexemplaren ist die Verzweigung fast

nach allen Richtungen hin verbreitet nur mit mehr oder weniger accen-

tuirter Neigung sich *in einer Ebene anzuordnen ; bei den im hiesigen

Laboratorium befindlichen, sowie bei den im Universitätsmuseum befind-

lichen Trockenexemplaren aus Bonin Inseln, die ich als der D. misaki-

mensis gehörend ansehe, sind dagegen alle Zweige nahezu völlig in

einer Ebene angeordnet, wie bei D. secunda. Als Unterscheidungsmerk-

male kommt jedoch einmal der Umstand, dass bei D. mzsakinensis einige

viel dickere Hauptzweige von den übrigen unterschieden werden können,

während bei D. secunda die Dickenverschiedeheit der Zweige bedeutend

zurücktritt, wie man aus der Vergleichung der Fig. 1 u. 7 (Taf. VI)

teilweise ersehen kann. Dann aber kommt noch der Unterschied in

der Farbe der beiden Arten: bei D. secunda nämlich sindd er Chitin-

teil schwarzbraun, bei D. misakinensis dagegen weisslich braun. Bei den

oben erwähnten Trockenexemplaren aus Bonin Inseln ist er zwar ganz

schwarzbraun wie bei D. secunda, aber diess ist meiner Meinung nach

entweder dem jahrelangen Trocknen zuzuschreiben oder doch wohl als

Localvariation anzusehen. Was die Querschnittsbilder der Zweige anbe-

trifft so erscheinen sie mir so unregelmässig und so viel der Variation

unterworfen dass man Unterscheidungsmerkmale der Arten daraus

nicht entnehmen darf. >

Die Polypen sind im ausgestreckten Zustand spindelförmig bei D.

misakinensis ; dagegen sind sie bei D. secunda stets cylindrisch.

Was den inneren Bau anbetrifft so bildet das Chitinskelett ein

Gitterwerk, so dass man in Schnitten Bilder von einem Netzwerk be-

kommt. In einem Querschnitt eines Zweiges von D. secunda ist das

Netzwerk überall fast gleich gebaut (Fig. 9); bei D. misakinensis kann

100 Ss. GOO.

man aber drei eile unterscheiden : einen Markteil (Fig. 3, 4), einen

inneren (b) und einen äusseren (c) Rindenteil. Im Markteil sind die

Maschen gross und die Trabekeln ziemlich dick, im inneren Rindenteil

sind die Maschen etwas kleiner and die Trabekeln am dicksten, im

äusseren Rindenteil sind die Maschen klein und die Trabekeln sehr

duno. In Natur sind diese Unterschiede noch frappanter als in der

Abbildung, da die verschiedene Dicke der Trabekeln eine ungleiche

Absorption des Lichtes hervorruft. Die Maschen sind etwas eckig

bei D. secunda, rundlich bei D. misakinensis, was jedoch nicht durchaus

constant ist.

Gehen wir nun zur Beschreibung des weichen Teils. Die Stämme

sowie die Zweige bis an die dünnsten sind zunächst nach aussen mit

einer Ektodermschicht umkleidet, und der chitinöse Skelettteil befindet

sich sämtlich nach innen von dieser ; nur da, wo die Trabekeln nach

aussen hervorspringen sind deren Aussenfläche bei D. secunda nur

durch eine äusserst dünne Ektodermschicht begrenzt; bei D. misakt-

nensis jedoch ist diese überall von ziemlich gleichmässiger Dicke.

Innerhalb dieses ektodermalen Ueberzugs liegen der Chitinteil und die

beiden Körperschichten, und zwar so, dass jedem Chitinstück zunächst

das Ektoderm und innerhalb dieses das Entoderm. Dieses letztere

stellt sich in Schnitten als rundliche oder verlängerte Röhren dar, und

fällt sehr leicht in die Auge, da seine Zellen mit groben, etwas lichtbre-

chenden, ziemlich stark mit Hematoxylin sich firbende Körnchen erfüllt

sind. In dünnen Schnitten, d. h. solchen wie man gewöhnlich mit dem

Mikrotom sich bereitet, gehen die einen jeden Entodermring umgebenden

Ektodermabschnitte verschieden in einander über, da in solchen Schnit-

ten die "einzelnen Maschen des Chitinskeletts nach dieser oder nach jener

Richtung offen sind; in dicken mit freier Hand verfertigten Schnitten,

wie sie in den Figg. 3 u. 9 wiedergegeben sind, wo jede Masche von ihren

Nachbarinnen völlig getrennt sich darstellen, sieht man dass die den

jeden Entolermringen gehörenden Ektodermabschnitte auch vonein-

ander getrennt sich darstellen. Zwischen den beiden Körperschichten

sowie zwischen den äusseren ektodermalen Ueberzug und dem nach

DENDROCORYNE. 101

innen davon liegenden Teil liegt die Stutzlamelle. Die Zellen des

Ektoderms sind sehr arm an Cytoplasma: entweder sind sie stark

vacuolisirt oder sie lassen grosse Intercellularräume zwischen sich. In

und zwischen ihnen kommen zahlreiche Nesselzellen vor ; dieselben sind

bei D. secunda von besonderer Grosse.

Nach der vorhergehenden Beschreibung sieht man dass das weiche

Gewebe unserer Tiere ein compactes Netzwerk bildet, ähnlich wie bei den

Milleporiden, nur das Netzwerk ist bei unseren Tieren noch dichter als

bei jenen. Das Skelett ist bei unseren Tieren chitinös, nicht kalkig.

In Fig. 10 sieht man die Anlage einer Knospe. Dieselbe bildet sich

zwischen den chitinösen Trabekeln, und legt sich so an, dass zunächst

‘ das Entoderm sich nach aussen hervorstülpt und das Ektoderm davor

weicht, wie bei der Knospung der Hydromedusen überhaupt.

An den Universitätsexemplaren von D. nusakinensis finde ich die

männlichen Gonophoren massenhaft. Dieselben sind kugelrund, mit

einem sehr kurzen Stiel versehen, und besitzen einen medusoiden Bau

(Fig. 5). Das Ostium kommt jedoch niemals zur Ausbildung, sondern

bleibt durch die Stützlamelle stets verschlossen. Radialkanäle sowie der

Ringkanal kommen nicht vor.

Die weiblichen Gonophoren von D. misakinensis kommen an den.

dem hiesigen Laboratorium gehörenden Exemplaren ziemlich zahlreich

vor. Sie sind länglich ellipsoidisch und mit einem deutlichen Stiel

versehen (Fig. 6). Das Ostium kommt zur Ausbildung ; aber es giebt

keine Radialkanäle, noch die Tentakeln, nur der Ringkanal ist ausgebil-

det, so dass man ohne Gefahr erschliessen darf, dass die weiblichen

Gonophoren niemals vom Mutterstamm getrennt werden.

Von D. secunda kennt man z. Z. nur die weiblichen Gonophoren.

Dieselben sind kugelrund, und mit einem sehr kurzen Stiel versehen.

Das Ostium ist sehr eng; der Ringkanal ist wohl ausgebildet, aber

soweit ich an dem mir vorliegenden, zwar nicht gut conservirten

Material ausmachen kann, kommen keine Radialkanäle vor, was die

INnABA” sche Angabe widerspricht. Das Velum ist ziemlich wohl ausge-

bildet, und die kurze Tentakeln kommen in der Vierzahl vor. Diese

letzteren sowie das Velum sind sämtlich nach innen gerichtet.

102 S. GOTO.

Nach dem Vorhergehenden fasse ich die Gattungs- sowie die Arten-

diagnose folgendermassen zusammen :

GENUS DENDROCORYNE, INABA 1892.

Hydromedusen mit stark gebauten, reichlich sich

verzweigendem Tierstock, dessen Chitinskelett ein

Gitterwerk bildet und von einer äusseren Ektoderm-

schicht uberzogen ist. Polypen sitzend, cylindrisch

oder spindelförmig; Tentakeln bis anf 20, an ihrem

Ende kugelförmig verdickt, unregelmässig zerstreut

am Körper. Männliches Gonophor soweit bekannt

medusoid, kugelrund, geschlossen, ohne Radial- oder

Ringkanal. Weibliches Gonophor kugelrund oder läng-

lich ellipsoidisch, medusoid, mit Ostium und Ring-

kanal, sowie zuweilen mit Velum und rudimentären

Tentakeln versehen.

l. D. misakinensis, Inaba 1892.

Tierstock reichlich nach allen Richtungen hin verzweigt, mit einer

Neigung sich in einer Ebene abzuzweigen ; mit einigen wenigen dicken

Hauptzweigen, von denen die düuneren sich abzweigen. Polypen im

ausgestreckten Zustand spindelförmig, von den Tentakeln 4—5 einen

Kreis um den Mund bildend. Weibliches Gonophor länglich ellipsoi-

disch, gestielt, mit dem Ostium und dem Ringkanal versehen, ohne

Radialkanäle. Männliches Gonophor kugelrund, geschlossen, mit einem

sehr kurzen Stiel. |

Chitinskelett äusserlich blassbraun, weicher wie bei der folgenden

Art. Fundort—Misaki.

2. D. secunda, Inaba 1892.

Tierstock reichlich in einer Ebene verzweigt. Polypen cylindrisch,

von den Tentakelıı 4—5 einen Kreis um den Mund bildend. Weibliches

Gonophor kugelrund, mit dem Ostium und dem Ringkanal, sowie dem

DENDROCORYNE. 103

Velum und 4 kurzen Tentakeln versehen. Männliches Gonophor unbe-

kannt.

Chitinskelett äusserlich dunkelbraun, stark gebaut.

Fundort—Misaki, Bonin Inseln.

Als ich Herrn INABA meine Uebersetzung seiner Originalbeschrei-

bung zuschickte, wurde ich durch ihn darauf aufmerksam gemacht,

dass die vorliegende Gattung vielleicht den 1868 von J. E. Gray!) als

Schwämme beschriebenen und von v. LENDENFELD? den Hydractini-

den zugezählten Gattungen Dehitella and Ceratella naheverwandt sei.

In der Tat ist Ceratella äusserlich unserer D. misakinensis sehr ähnlich,

Dehitella dagegen der D. secunda. Da aber die Entscheidung dieser

Frage erst nach Vergleichung mit den Originalexemplaren möglich ist,

so verschiebe ich diese auf eine monographische Arbeit über Dendroco-

ryne, die ich in Absicht habe.

Ich sehe unsere neue Gattung als Vertreterinn einer neuen Fami-

lie an, und schlage dafür den sachgemässen Namen : Deudrocorynidae

vor.

Am Schluss möchte ich die Paleontologen darauf hinweisen, ob nicht

der Bau jener alten Petrefakten, der Graptolitiden, im Lichte der

Strukturverhältnisse des Chitinskeletts unserer Tiere besser verständ-

lich werde.

1.) J. E. Gray— Notes on the Ceratellidæ, a family of Keratose Sponges. Proc.

Zool. Soc. London, 1868, p. 575—579.

2.) R. vy. LENDENFELD— Ueber Coelenteraten der Südsee. V. Die Hydromedusen des

australischen Getietes. Zeitschr. f. wiss. Zool., Bd. 41, 1885, S. 657.

104 Ss. GOTO.

'TAFELERKLARUNG.

Dendrocoryne misakinensis.

Fig. 1. Ein kleiner Tierstock 1/;.

2. Spitze eines dünnen Zweiges. 54/,.

3. Ein 'l'eil eines Querschnittes des Stammes; nur der Chitinteil ist abgebil-

det. 54/.

4. Ein kleiner ‘l'eil eines Querschnittes durch einen dünnen Zweig.

5. Schnitt durch einen dünnen Zweig samt dem darauf sitzenden männlichen

Gonophor. Chitinteil schwarz, Entoderin dunkel schattirt, Ektoderm

250/..

schwach schattirt. 56/..

6. Längsschnitt eines weiblichen Gonophors. Schattirung wie in Fig. 5. 5/1

Dendrocoryne secunda.

Fig. 7. Ein kleiner ‘l'eil des Tierstocks, 1/1.

8. Spitze eines Zweiges. 54/,.

9. Querschnitt durch einen dünneren Zweig; nur der Chitinteil ist abgebil-

det. 1186/,.

10. Ein kleiner Teil eines Querschnittes durch einen dünneren Zweig.

ll. Längsschnitt durch ein weibliches Gonophor ; Schattirung wie in Fig. 5. 86/1.

250/1,

Abgedruckt 27. Juli, 1897.

D A000. JAP. Non I

ANNO

TAR. VI

SIERT

> eine - — am e « Ve PE on 2 Ti

On a New Species of Malacobdella

(M. japonica).

By U. Takakura.

Zool. Institute, Imp. University, Tokyo.

With PI. VII.

Since last April I have devoted myself to the investigation of a

Malacobdella, which lives in the mantle cavity of Mactra sachalinensis,

Japanese name, “ Ubagai” or “ Hokkigav’, and ,have found out that

notwithstanding a close resemblance of its external form to that of M.

grossa, Miller, its internal structure presents some features sufficiently

different from that of the latter species, to justify its separation into a

distinct species.

M. japonica, as I propose to call our species, lives in the mantle

cavity of Mactra sachalinensis, which is found in the northern part of

our country. The specimen I used were all collected on the shore of

Kujükuri on the Pacific coast of the province Shimousa. Almost every

individual of Mactra from that locality contains the parasite. Of the

56 shelis, which I examined, 54 were found to be infected. As v.

KENNEL found in Cyprina islandica, adult worms live always single

in one shell, while if two or more live together in one shell these

are invariably young individuals. Of the 54 shells, which contained the

parasite, one was infected by 7, and two by 4, individuals which were

all very young.

The longest specimen of M. japonica is about 45 mm. long and

4 mm. broad when fully extended, and the cesophageal region is broader

than the posterior. When contracted, its length is reduced to nearly

one-half, and the posterior part of the cesophageal region is slightly

concave. The ground color is dark yellow.

106 U. TAKAKURA.

In the epithelium are found flasc-shaped glandular cells, whose con-

tents stain with hematoxylin. They are generally numerous on the

ventral side, while they are often entirely absent on the dorsal surface

and on the very tip of the head. Under the muscular layer of the

body-wall in the anterior region, numerous groups of glandular cells

are imbedded within the pareuchymatous tissue. In most specimens,

these groups are found in the cesophageal region, but sometimes they

extend far behind that part. Generally they are found in a great

number on the dorsal side. The ducts of these glands can not be

clearly observed, but it seems probable that the streaks of fine granules,

which are visible among the epithelial cells of the body-wall and which

appear to have the same nature as the secretion of the glands, indicate

their external ducts. At the anterior upper and lower edges of the

mouth, their external ducts can distinctly be observed passing through the

basal membrane to the exterior. In a greater part of the dorsal and

ventral sides of the flattened lateral portion of the cesophageal region

these glands are much developed, but few of them are met with in the

anterior. Along the margins of such lateral portion, a voluminous

aggregation of them is situated on each side, and their external ducts

open at the lateral edge. These glands are abundant in the acetabulum

as in M. grossa, especially on its ventral side.

The wall of the cesophagus is folded into finger-like processes, which

v. KENNEL and others have already noticed ; when fully extended they

become rather slender, and those of the anterior part are protruded

out of the mouth opening, and are moved to and fro like tactile

organs. These processes, however, become short in the posterior and

vanish in the narrow region, which connects the oesophagus with the

intestine. The epithelium of the oesophagus is provided with a thin

tunica propria, as BÜRGER observed, and the sub-epithelial glands are

loosely imbedded on the outside of it, deeply within the body

parenchyma. They are most numerous a little in front of the end of.

the oesophagus. ‘The intestine, which is clearly distinguished by a

narrow constriction from the cesophagus, makes about 10 windings, not

ON A NEW SPECIES OF MALACOBDELLA (M. JAPONICA). 107

having diverticula. The anus opens dorsally nearly at the center of

the acetabulum. .

The rhynchocælom of the present species differs greatly from that of

M. grossa by being short (pl. VII, fig. 1). v. KENNEL says : the structure

in the latter species “ bis zum letzten Drittel des Köpers deutlich sichtbar

bleibt,” and “ sondern jene (Biegungen des Darmes) manchmal schneid-

end bis gegen das Hinterende des T'hieres hin, wo sie sich bei macros-

copischer Betrachtung verlieren.” BURGER remarks also : “ Malacobdel-

la ist mithin eine Angehörige der Holorhynchoccelomier.” hus

in M. grossa it is obvious that the rhynchoccelom reaches the posterior

end of the body, but the Japanese species is never a “ Holorhyncho-

coelomier.’ The rhynchoccelom extends in the first two-thirds of the

body and its posterior extremity is macroscopically distinctly observed.

Different from M. grossa, a microscopical examination shows that it does

not extend further backward than can be observed from the surface. Lt is

slightly winding, being situated on the dorsal side of the digestive canal,

but does not follow the curvature of the latter precisely (fig. 1). The

proboscis, which has nearly the same length as the sheath, is

distinguished into the anterior long glandular portion and the posterior

short bulb-like cavity, followed by a strong retractor. The wall of the

bulb is much thinner than that of the anterior division. The inner

epithelium consists of low cylindrical cells, without glandular elements,

and is not “ganz flaches Pflasterepithel” as v. KENNEL noticed.

The retractor muscle is a strong bundle of longitudinal muscle fibres,

which reaches the hind end of the rhynchoccelom, Its posterior ex-

tremity not only reaches the narrow end of the latter, but passing through

its wall enters the parenchymatous tissue surrounding it and is soon

reduced in bulk. Of the termination of the retractor fibres of M. grossa,

it is said that they, after passing through the end of the rhynchoccelom,

rise dorsad to be affixed to the muscular body wall, but the case is

quite different in the present species. Instead of proceeding dorsad,

they bend rather ventrad, and no connection with the muscular body

wall is observed, except their crossing the dorso-ventral fibres, and

108 U. TAKAKURA.

they terminate freely in the parenchymatous tissue (fig. 2). BÜRGER

noticed the undoubted existence of the proboscis nerves between both

longitudinal muscle layers, but he did not enter into further detail. As

far as my investigation goes, it is most probable that the “ Bindegewebe

mit zelligen Elementen,” which is alluded to by v. KENNEL represents

the nervous layer of the proboscis.. It has no definite form as in other

Metanemertini, and is sometimes swollen and sometimes constricted,

and often gives off several processes between bundles of muscle fibres.

Numerous oval nuclei are imbedded within, or in the peripheral part of,

the granular looking substance, which would be the fibrous part of the

nervous layer. Such granular portion presents similar appearances as

the fibrous part of the nervous system and has the same affinity for

hematoxylin or eosin.

The circulatory system shows very complex anastomoses, and

approaches the condition described by BLANCHARD” and HorFMANN,” yet

differs from them in some points. In young specimens it consists of

only three vessels, one dorsal and two lateral, as in other Metanemertini,

and has already been noticed by several authors (fig. 1} The two

lateral vessels are connected in the head by a transverse canal and

joined in the anal portion to two branches of the dorsal vessel (fig. 1).

The dorsal vessel arises anteriorly a little behind the ventral commissure

of the brain, by the fusion of two branches from the lateral vessels. At

this stage there is not yet any branch to be found. But in the adult,

the circulatory system reaches a degree of complication never found in

other nemerteans, by giving off numerous branches, which come to

anastomose with one another, especially in the anterior region. Figs. 3, 4,

and 5, which have been reconstructed from sections, show respectively the

circulatory system in the cesophageal, the middle, and the anal region.

The vessels invariably show a complex system of anastomoses and are

very asymmetrical, although there seems to be a great deal of individual

variation. The dorsal vessel (fig. 3, d. v.) does not appear to be

1) & 2). I have not had access to the works of BLANCHARD and Horrmann, but I

gather the above from the references made by v. KENNEL.

ON A NEW SPECIES OF MALACOBDELLA (M. JAPONICA.) 109

derived directly from the laterals as in the young specimen, but there

seems to be various interplaced canals. It gives off in its course several

auastomosing branches of various sizes, and such branches are connect-

ed laterally to those, which are derived from the laterals and occupy

the lateral portions of the body (fig. 3, net. v.). In the anterior and

middle regions the vessel can more or less distinctly be discriminated

from its branches by its position under the rhynchoccelom, though it is

often obscured in the middle region, where it makes strong windings

and have large branches. In the anal region, however, it is im-

possible to trace the vessel as a single canal as in the anterior region,

for it becomes slender connecting canals, traversing between the two

large vessels (fig. 5, d. v.) above the intestine, and does not take the

median position. These two vessels are continuations of those which

are observed in other portions on the side of the dorsal vessel, being

fused together with the latter at several points (fig. 4, d. v.).

Laterally these two vessels are continued to a network of small canals,

situated in the lateral part of the body, as in the anterior part (fig.

4 & 5, net. w.). At the end of the body they are united into a single

canal and the lateral networks nearly disappear. Sucha single canal

divides, however, into two, immediately in front of the anus, and each

branch enters the acetabulum to communicate with the lateral of its

own side, and forms two curved vessels (fig. 4, ac. v.), which run

along the edge of the acetabulum. Besides the horizontal windings, the

two large vessels above stated make in their posterior portion strong

vertical undulations along the sides of the digestive canal, approaching

very near the lateral (fig. 4, /. v.), which is situated on the ventro-

lateral edge of the intestine, yet there are only a few direct con-

nections between the laterals and the large vessels in consideration.

In the anterior region, some of the branches of the dorsal vessel always

run among the muscular fibres of the proboscis sheath, and com-

municate at several points with the dorsal itself. These branches

already exist in young specimens, whose vascular system is furnished

with only a few anastomosing branches in the tip of the head. The

110 U. 'TAKAKURA.

lateral vessels (/. v.) are generally recognized everywhere, by their

greater sizes and paucity in branches except in the cesophageal

region. They are situated on the ventro-lateral sides of the digestive

canal, except in the head, where they gradually shift their positions

dorsad and finally take the lateral position, In the cesophageal

region, varlous anastomosing branches are separated off towards

the outer and imner sides and spread in the flat laterai edges of

the body. It is through these canals that they are indirectly con-

nected with the dorsal vessel. Atthe tip of the snout, the numerous

branches also form networks, which are posteriorly continued to those

in the lateral edges. Some branches from the vessels form a canal

system which occupies the ventral side of the body. In fig. 3,

this ventral canal system is shaded. Sometimes ventral con-

nections under the cesophagus join the canals of the opposite

sides (v. c.), a fact hitherto not noted in Metanemertini. The system

is connected in several points to that (not shaded in the figure)

situated on the dorsal side. In the middle region, the lateral vessels

have only a few branches (fig. 4, 7. v.). Unhke those of M. grossa,

they have no branch at the posterior region, and in the acetabulum no

trace of a complicated vascular system, as described by v. KENNEL, is

found.

Of the excretory system no essential difference can be detected in

the present species, except that the external opening is not situated

ventrally, but dorsally to the lateral nerve stem and opens at the

dorso-lateral side of the body.

The peculiar feature of the nervous system is the position of the

posterior commissure of the lateral nerve-stems. There is no trace of

the anal commissure above the anus, but posterior to it, along the

posterior margin of the acetabulum, a strong commissure is distinctly

observed as shown in figs. 1 & 6(«. ¢.). At the points, from which the

lateral nerve-stems enter the acetabulum, they slightly become larger,

as v. KENNEL observed, and between these points a slender commis-

sure runs along the anterior side of the acetabulum (ac.c.). This

ON A NEW SPECIES OF MALACOBDELLA (M. JAPONICA). 111

commissure gives off numerous branches internally and externally, and

together with the several big twigs from the larger commissure

innervate the acetabulum. The ganglionic cells are found in the larger

acetabular commissure.

Thus the Japanese species of Malacobdella mainly differs from M.

grossa by its short rhynchocelom, by its possessing the acetabular,

instead of an anal, commissure, and by some differences in the vascular

system. These data, I think, are enough to separate the present

species from M. grossa.

July 1897.

112

(5)

Fig.

U. TAKAKURA.

LITERATURE.

V. KENNEL—Beitriige zur Kenntniss der Nemertinen. Arbeit Zool.-Zoot. Inst.

Würzburg Bd. IV, 1878.

A. C.Oupemans—The Circulatory and Nephridial Apparatus of the Nemertea.

Quart. Journ. Micro. Sci., Suppl., 1885.

A. E. VeRRILL—Marine Nemerteans of New England and Adjacent Waters. Trans.

Connect. Acad. vol. 8, 1893.

L. Jougın—Les Némertiens, 1894.

O. BÜRGER— Die Nemertinen des Golfes von Neapel, 1895.

EXPLANATION OF FIGURES.

AC, large acetabular commissure. «c.c. small acetabular commissure.

ac. v. acetabular vessel. an. anus. b.v. blood vessel. d. v. dorsal vessel.

D’.V. large branches of the dorsal vessel. in. intestine. /.v. lateral

vessel. net. w. net-work of canal system.

Oes. esophagus. Pr. proboscis. Ih. Rhynchocælom.

Ret. Retractor muscle of the proboscis.

Dorsal view of young II. japonica.

Vertical section of the end of the rhynchocelom.

Blood vessels in the head of the adult, reconstructed from sections; Md

median line. The vessels on the ventral side are shaded.

Blood vessels in the middle region of the adult, reconstructed from

sections.

Blood vessels in the anal region of the adult, reconstructed from sections.

Vertical section of the anal region, showing the acetabular commissures

of the lateral nerve stems.

Printed July 25, 1897.

Notes on the Breeding Habit and

Development of Racophorus

Schlegelii, Gunther.

By S. Ikeda.

Zoological Institute, Imp. Univ., Tokyo.

The breeding habit of one of our tree-frogs, Racophorus Schlegelii,

Günth., present some remarkable features not known, so far as I am

aware, in any other amphibia, and no apology, I believe, is needed for

the publication of the following notes.

It is now thriteen years ago that my attention was first called to

the peculiar breeding habit of this tree-frog. When I was travelling

in 1884 through the Aizu district in the province of Iwashiro, I came

one day across a pair of the tree-frogs depositing eggs in soft muddy

ground covered with grass. ‘The egg-mass was of a very peculiar ap-

_ pearance —it was a frothy mass, about 6 or 7 cm. in diameter, full of air-

bubbles, looking exactly like well-beaten white of hen’s egg. Pale

yellowish eggs of the frog were scattered throughout the mass.

I have since been able to find in Tokyo the frothy egg-masses of

the same species imbedded in wet and muddy banks of paddy-fields,

ponds, etc. and to continue my observations on the breeding habit from

year to year. Some of the results I have already published in the Tokyo

Zoological Magazine in Japanese. It has, however, been only within the

season just past that I have had the joy of ascertaining exactly how the

frothy mass is produced. What is stated in the sequel have been com-

piled mostly from these observations made in Tokyo.

JJ4 S. IKEDA.

Pairing and Deposition of Eggs.

The breeding season of Racophorus Schlegelii extends from the

middle of April to the middle of May, the exact time varying from year

to year according to meteorological conditions. It seems most probable

that a certain mumber of both males and females wake up from their

hybernation on every warm day or night during the season, and soon

pair on that day or the next. Therefore at such times we often find soli-

tary individuals here and there in shallow waters of paddy-fields or ponds,

some of these repeating a peculiar cry “ kro-kro-kro, kro-kro-kro.”

This is the sexual call of the males, which keep themselves hidden among

grasses or in water and utter these notes elevating their heads a little.*

The females are always larger than the males. The length in the

median line of the former measures about 5—6 cm., while the latter rarely

exceed 3—4 cm. Once I came on a funny sight of a large female 6 cm.

long pairing with a male of 2.5 cm. It seems probable to me that

the selection of partners is done mostly during the day time and that,

towards the evening the female bearing the male on her back retires

under ground to prepare for the deposition of eggs. If, however, the

temperature should suddenly rise towards evening or during night

after some cold days, then partners may be secured during the night, for

at such times we often hear the sexual calls at night. After one or more

cold days, it is difficult to find any animals either solitary or in pairs, or

to find any fresh egg-deposit.

*This species has another call. In summer it utters a ery “kiak-kiak-kiak, kiak-kiak-

kiak,” and this appears to me to be uttered by both males and females. ‘he time and

duration of the breeding season, and the sexual call of this species differ in many points

from those of our Rana and Bufo. The breeding season of Rana temporaria is found in

Japan to be a week or fortnight from the end of February to the beginning of March, and

the tone of its sexual call is higher and longer than that of Racophorus. The breeding

season of Bufo japonica is in the end of March or the beginning of April and lasts also a

week or fortnight. Its sexual call is louder and higher but shorter. ‘The pairing of Bufo

is generally effected on warm nights or days during the season, on land, and then the

animals go into water for the deposition of their eggs. The breeding season of Rana

rugosa is in Japan, in the middle or the end of June, and goes on also a week or fortnight,

and its sexual call resembles somewhat that of Racophorus, but is a little higher in tone.

BREEDING HABIT AND DEVELOP. OF RACOPHORUS. 115

The place where the partners retire to deposit eggs is always, so far

as my certain observations go, in wet and muddy banks of paddy-fields,

ponds, lakes, and the like. The spots chosen are generally along such a

bank, at 10—15 cm. above the surface of the water, so that there is no

fear of being washed by it. The site being fixed, the female digs in the

muddy ground a spherical hollow 6—9 cm. in diameter. The inside of

the hollow is made somewhat smooth by the movements of the female.

Thus the auimal that performs the chief work is the female who bears

the male on her back, and moves round in the hollow, pressing its body

against the wall. ‘The hollow thus formed, the animals retire into it;

and then it is entirely concealed under ground, being generally covered

with grass. It is, therefore, very hard for one who is not well ac-

quanted with the habits of the frog to find out such a hollow. The hol-

low is not, however, situated very deep under ground, and a part of the wall

tarned toward water is generally formed by a thin sheet of earth particles

or dry mud, so that by boring through this part the animals may leave

the hollow when they have finished the egg-deposition. The only

way to find out such a hollow is to grope patiently by hand, along a

bank which one thinks a favorable locality ; when the hand goes into a

hollow and comes in touch with the frothy egg-mass, a sort of gushing

sound, which is produced by the crushing of the air-bubbles, is heard. The

animals in the hollow are dark colored, different from the green color

which they assume on trees or among dense grasses.

In general, when a night is warm, the animals sheltered as above

finish spawning by the next morning, but if the night is cold, the egg

deposition may be delayedand done either during the next day or at

night, the latter, however, being much more frequent.

The foregoing account is sufficient to show that the deposition

of eggs in this species takes place almost always during the night.

It is probable that the selection of partners, the digging of hollows,

and the deposition of eggs are all accomplished in a single day and

night, after their awakening from hybernation.

When the deposition of eggs is finished, the pair separates and

116 S,.. IKEDA.

each goes out of their hollow, leaving only

eggs init. Once or twice, I have seen

the female alone remaining behind in the

hollow. As tothe mode of life after

separation, Racophorus Schlegelii pursues

one different from that of Rana or Bufo.

The animals belonging to the latter genera

go again under ground or into the bot-

tom of deep water and there rest awhile,

while the present species, after breeding,

directly creeps out above ground and then

goes upon the leaves or twigs of trees,

uttering their peculiar summer call.

I have said above that the place selected for the deposition of eggs

is, so far as my certain observations go, in wet and muddy banks of

paddy-fields, lakes, and the like. I used the italicized clause advisedly,

for there are indications of the animal depositing eggs in other localities.

When living in my native province Echigo, I often noticed a species of

green tree frog depositing its eggs between twigs and leaves of trees

standing near water or among grasses growing near ponds, paddy-fields,

etc. These eggs, I remember, were always enclosed in a frothy mass

full of air-bubbles: My friend, Mr. M. Kixucat, tells me that he once

saw a similar egg-mass on a shrub growing by the side of the pond in

our University grounds in Tokyo. Mr. Y. TAKAHASHI, I am told, once

noticed in the Hakone mountains a similar mass that was falling from a

tree into a water-pool below. Some others of my friends have often

found the same kind of frog-nests on trees in Nikko. One of the cases

at the last mentioned locality has been described: in an article entitled

‘“ Arboreal Tadpole’ by an American naturalist, Mr. W. J. HoLLAND

(American Naturalit, vol. XXIII, May 1889, p, 383), who expresses

evident surprise at the peculiarities of the nest. Although I have not

had opportunities of examining the frog in any of these cases, it seems

very probable that all these frothy nests belong to Racophorus Schlegelii,

BREEDING HABIT AND DEVELOP. OF RACOPHORUS. ale

and that this species deposits its eggs under ground as well as on trees,

shrubs, and grasses.

Egg-mass.

The eggs, when laid as stated above, are enveloped in a white

jelly-mass full of air-bubbles, and of a spheroidal form. The surface of

the mass is generally dirty from mud and earth particles adhering to

it, while the interior remains pure white. The bubbles in the jelly

mass vary in size, but are commonly 2—3 mm. in diameter, and are

spherical in form. The snow-like appearance of this mass is entirely due

to the presence of bubbles, as the fact that certain portions free from

them remain transparent well proves, so that the comparison of such

a mass to froth formed of well-beaten white of hen’s egg is more than

superficial. The newly laid mass is very elastic and tenacious, but with

the lapse of time, it becomes gradually less elastic and less tenacious, so

as to run down. The mass is then no longer able to keep its shape and

flattens down gradually with the loss of air-bubbles in it, until finally it

becomes so liquid as to flow out of the hollow into the water. By

this time, the eggs have hatched into tadpoies, which are of course

adapted to hfe in water. The outlet, through which the melted mass

of the jelly runs down into the water, is the orifice previously made by

the parents when they went out of the hollow through the thin portion

of its wall above mentioned. ‘I'his circumstance beautifully explains

the reason why the egg-nests are never placed far from water. Both

too much wetness and dryness seem equally injurious to the development

of eggs. Those that have not yet hatched can never thrive in water,

and if placed artificially in it by way of experiment, they soon die. On

the contrary, I once saw some years ago, at Echigo, a nest of the

species hanging down about 2 feet above water between the leaves of Jug-

lans Sieboldiana (.Jap—Onigurumi) near the bank of a ditch; it was

entirely dried up like a piece of dry bread, with many dead eggs in it.

What purpose does this frothy envelope of eggs serve? I am

inclined to answer the question as follows :—

118 S., „IKEDA,

(1) It protects the eggs, mechanically, from external agencies.

(2) It perhaps prevents the eggs from too much crowding.

(3) It is made especially, as I think, to facilitate the respiration

of the eggs and embryos in their early developmental stages.

The first of these points is very obvious. The jelly-mass around

the eggs of Bufo, Rana, Salmandra, and the mass around the sepa-

rately deposited eggs of Triton, must all serve the same protecting

purpose. Small air-bubbles must act in this case as a sort of cushion,

and are well adapted to protect the eggs out of water. As to the second

point in Bufo, Rana, Salmandra, and others, in which eggs are deposited

in groups in water, the jelly-mass around each egg absorbs water and

swells up gradually, thus preventing the eggs from coming into contact

with one another. In the present case, the mass of eggs being deposited

under ground or in air out of water, the jelly can not swell up as

much as 1n other cases, and it seems probable to me that the function of

the air-bubbles within the jelly-mass is, in part, the means of prevent-

ing the eggs from too much crowding. ‘The third point must surely

indicate the chief purpose of this frothy envelope. The jelly-mass in

this case is more hable to dry than those of the other amphibians,

since it is not in water. And when the outer surface of the jelly-mass

is dessicated and forms a crust, it effectually protects the inner part

from further evaporation; but at the same time the inner part must

necessarily be excluded from the external air—a condition which would

cause the death of the eggs and embryos but for the presence of such

air-bubbles as we see in this species.

Now comes the question: how is this peculiar frothy envelope

produced? It is a question to which I have given much thought and

attention, and the answer to which I have tried to find out every succeed-

ing breeding season for some years past. All my efforts were baftled

until last spring, when at last I was rewarded with success. The

breeding season was somewhat backward this year, and on the afternoon

of April 26, I found and brought home, besides some masses of eggs,

a pair of frogs that were together in a hollow. This pair could not

BREEDING HABIT AND DEVELOP. OF RACOPHORUS. 119

have beed long in the hollow, for the latter was not yet completed in

some respects. Warned by previous failures, I placed the pair gently

in an already prepared glass-jar and covered it with apiece of black

cloth, allowing an observer to peep in only from two opposite sides. I

took the jar on my table and sat watching the animals until eleven

o'clock at night. But the animals were no doubt frightened by abnormal

conditions and could not be induced to deposit eggs. On the next day

(the 27th.), however, when I returned home at 6 P. M. I found that the

animals had just begun spawning. The frothy mass was only about

3 em. in diameter and contained about 20-30 eggs. The female was

incessantly contorting her body. In order to watch these movements

more satisfactorily, I lifted up slightly one end of the cloth-cover, but

the instant I did so, the female ceased her movements aud retreated

into the frothy substance behind her. After these manceuvers were

repeated two or three times on her part and mine, I boldly took away

the cloth wholly from the jar. At first, the female hesitated, but after’

some time she began to deposit eggs, as if she did not mind light at

all. Now, at last, my wish of many years standing was gratified and

I could make exact obsevations.

The act of pairing in this species is not performed differently from

other anurans, but the positions and movements of the hind limbs in

both the male and female are very characteristic of the species. When

the female is at rest, with the male on her back, the anterior part of

her body is raised on the anterior limbs, but the posterior part of the

belly lies flat on the floor and the loin is lowered so that the ventral

margin of the cloaca comes into direct contact with the floor. The

three portions (the femur, the crus, and the pes) of ber hind limbs

assume the following peculiar positions: the femur is directed anteriorly

and externally, its lower surface (at least its proximal portion) touching

the floor ; the knee is flexed as much as it can be, so that the crus comes

to lie dorsally to the femur, and the ankle-joint is drawn on the back of

the animal, on the side of the posterior part of the urostyle. The

aukle-joint is also deeply flexed and the distal part of the pes touches

120 S. IKEDA.

the floor. It is through the movements of the posterior limbs of the

female that the frothy mass is kneaded and formed, but the parts moved

are confined for the most part to the crus and the pes, the femur remain-

ing comparatively still The movements are not, however, by any

means simple. Sometimes the knee and the distal end of the pes being

fixed, the ankle-joint is moved backward towards the cloaca, just at the

same time that it is flexed. Sometimes the ankle-joint is more or less

straightened out and the crus and pes are thrown strongly backwards,

the pes of the two sides often crossing each other. Corresponding parts

of the two sides move simultaneously. The toes also perform an

independent motion of their own ; they are strongly flexed, as if they were

grasping some object. When any one of the motions is begun, it is

generally repeated 5 or 6 times in succession, for about a minute. A

rest of about half.a minute follows a series of these motions, before

another is begun.

Let us now see in what relation these motions stand to the produc-

tion of the frothy envelope. While these motions are rapidly going on,

the eggs together with the jelly-mass are gradually forced out of the

cloaca, and are laid down on the bottom of the jar. When the ankle-

joints or the crus and pes of both hind limbs are flexed backwards over

the newly deposited jelly-mass, the latter easily adheres to the surface of

the joints and of the pes, as it is very viscous. When the joints are

again moved forwards to their positions on the back of the animal, the

jelly adhering to them is pulled out as a thin transparent membrane

stretching between the ankle-joints and the proximal part of the pedes of

the two sides. When the joints are in the next motion again thrust

backwards, the thin membrane is folded downwards and becomes a large

vesicle about !/,—1 cm.in diameter, as the annexed woodcut shows.

The air that forms the vesicle seems to enter from the sides, helped on

by the grasping motions of the digits. ‘These large vesicles are formed

successively and carried back with each motion of the hind hmbs. The

large vesicles thus driven back are gradually broken up into smaller

and smaller bubbles by the stirring of the crus and pes, when these

BREEDING HABIT AND DEVELOP. OF RACOPHORUS. 121

are thrust back. It may appear strange

that these treading and kneading mo-

tions do not injure the eggs, but when

we consider that they are covered over

with highly elastic and tenacious jelly

full of air bubbles acting as a sort of

cushion, the safety of the eggs is not

so mysterious as may appear at first

sight.

Fig. 2.

AB—a thin membrane seen in the

sagittal section. AC D E—a vesicle

produced by the folding of the

membrane AB.

The hind limbs of the male on the

back of the female are bent in a vertical

plane. The knee which is strongly

flexed is inserted between the anterior margin of the femur and the sides

of the belly of the female. ‘The crus and pes are moved as a whole

dorso-ventrally, thus stroking the pelvic portion of the female. This

motion on the part of the male, it seems to me, is probably done in

order to assist, by stimulation, the egg-deposition of the female. In

some instances, however, another sort of motion was often gone

through by the hind limbs of the male, in this way, viz. the hind limbs

are withdrawn from the above mentioned position and soon thrown

back, the crus and pes rubbing the dorsal face of the loin and cloaca

of the female. Sucha motion of the male hind limbs seems to me to

be done to clear away the jelly particles adhering to the region in

question of the female, which possibly interfere with the safe passage

of the sperm-fluid.

Eggs and Embryos.

The eggs in the frothy mass differ more or less in size according to

that of the mother animal, but in general they measure about 1 mm.

in diameter, and are at first free from any pigment, which appears only

later at the tadpole stage. The yolk pole is yellow, while the animal pole

is merely pale and somewhat translucent. The very thin structureless

yolk-membrane is closely applied to the egg, around which the jelly-

122 S. IKEDA.

mass is devoid of bubbles and shows, to a certain extent, a concentric

arrangement. The pigment appears first at the pectoral region of the

hatched larva, as in the case of fish-embryos.

Segmentation on the whole is unequal and total, but it shows «

greater approach toward the meroblastie mode than other amphibian

eggs ; the first horizontal cleavage plane (3rd.) is placed nearer the upper

pole and encircles a smaller area than in the eggs of Bufo and Rana.

The first and second meridional cleavage planes may reach the yolk-pole,

where they often cross with each other, but the subsequent meridional

cleavage planes do not reach the yolk-pole and end mostly at about the

equatorial region of the egg. Moreover at a later stage of development

the first two meridional cleavage planes, which once reached the

yolk-pole, become more and more insignificant up to the 32- or 64-cell

stages, when they entirely disappear, together with some other cleavage

planes in the lower hemisphere, while the cell outlines of the upper

half are still distinctly visible.

The early development of the embryo is quite different from that

of other amphibians, but resembles very much that of the ganoid, which

is indeed the point that roused my great interest in the development

of the animal several years ago, when I was studying the embryology

of other amphibians under the direction of Prof. K. Mitsukuri. The

chief points of resemblance with the ganoid are as follows: (1) the

embryo is greatly flattened over the large yolk-mass, so that the ven-

trally observable organs, as the heart and the hyo-mandibular arches,

appear in front and at the sides of the head ; (2) the body of the embryo,

in later stages, is wedged into the yolk-mass, which is deeply grooved

along the dorso-median line.

There are many other points which must be studied comparatively

with the ganoid, the teleost, and other fishes. I have, however, not yet

finished the microscopical study of these eggs and embryos. It is

my earnest hope to be able to return to this subject at a later date.

na Printed July 27, 1897.

Miscellaneous Notes.

Zoological Society of Tokyo.—l'he monthly meeting of the Society

for April was held in the lecture room of the Zoological Institute of the

Imperial University at 2 P.M. The President in the chair. The

following papers were read :

Dr. KisHINOUYE on “a Trip to Tottori Prefecture.” The author

dwelt on the routes to this part of the country and gave a general ac-

count of its fauna.

Prof. SASAKI on “ Pebrine.” After giving a brief historical survey

of previous works done on this disease of the silk-worm, in which he

referred specially to those of PASTEUR and BALBIANI, he communicated

the result of his own investigation as to the trne nature of the micro-

organisms that cause the disease. According to it those minute corpus-

cles that are found floating in the blood of the infected silk-worm repre-

sent only a stage in the life-history of an amoeba-like organism, in other

words, those corpuscles are spores, thus confirming the result obtained

by BALBIANI as opposed to that of PASTEUR.

The meeting adjourned at 3.30 P.M.

The monthly meeting of the Society for May was held at the usual

place at 2 P.M. . The President in the chair. The following papers

were then read :

Mr. NisHikawa On “the Embryology of Caprella.” The author

gave a detailed account of the segmentation, gastrulation, and the for-

mation of the mesoderm in a species of Caprella common in winter

among Sargassum in Misaki, and compared them with the same pro-

cesses in other crustaceans.

Prof. Harr on “the Development of the Heart in Petromyzon.”

An abstract of this paper is promised in the next number of this

periodica).

The meeting adjourned at 4 P.M.

The monthly meeting of the Society for June was held at the usual

place at 2 P.M. The following paper was read :

Prof. Mrrsuxuri on “the Species of Holothurians manufactured

. 124 MISCELLANEOUS NOTES.

into Kinko* in Japan.” The following species were enumerated -

Miilleria mauritiana, Quoy et Gaim., M. variuns, Sel., M. miliaris, Q.

et G., M. lecanora, Jiig., M. formosa, Sel., M. nobilis, Sel., M. sp., Cu-

cumaria japonica, Semp., Stichopus japonicus, Sel., St. sp., Holothuria

monacaria, Less., H. decorata, v. Marenz., H. tenuissima, Semp., and

H. fusco-cinerea, Jag.

The New Imperial University of Kyoto.—By the Imperial Ordi-

nance, No. 209, of June 18, a New Imperial University has been incor-

porated in Kyoto, with ninety professorships, forty-one assistant-professor-

ships, and a provision for ninety assistants (Imperial Ordinance, No. 210).

It is to consist of the four affiliated Colleges of Jurisprudence, Medicine,

Literature, and Science and Technology. Only the College of Science

and Technology will be opened next fall, and the chairs for it has been

ordained to be twenty-one, distributed as follows: Mathematics 2,

Physics 3, Chemistry 4, Civil Engineering 3, Mechanical Engineering

3, Electrical Engineering 2, Mining 2, Metallurgy 2. We thus see that

the department of pure Natural History has been wholly left out ; but

we hope that this anomalous state of things will be but temporary, due

entirely to financial deficiencies. We have every reason to believe that

in a near future all ‚the principal branches of modern science, whether

pure or applied, will be fully represented by an adequate number of

chairs ; and we would suggest that when our science should be represent-

ed in the New University, a fresh water station on Lake Biwa would be

a very fitting adjunct calculated no doubt to contribute much to the

collecting of valuable informations as to the biological conditions of large

bodies of fresh water, on which so much excellent work is being done

both in Europe and America. |

* Dried holothurians used for food.

PRINTED AT THE “'l'oryo Prinvine Co. Lp.” Torro, JAPAN.

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CONTENTS OF LAST ISSUE.

—_ Ma en

e... ee. Mitsukurt ..... 1

Pear-borer (Nephopteryx rubrizonella, Rag.).........M. Matsumura... |

On Two New Species of Asthenosoma from the

D AMD +... De OSNwAaTa... 5

Chaetognaths of Misaki Harbor...................... m Addas....: Biles 13

On the Accommodation of Some Infusoria to the

Solutions of Certain Substances ın Various

VORESNETANONS. San 001 OR A MUSA ae 23

On Changes which are found with Advancing Age

in the Calcareous Deposits of Stichopus

PAPOMICUS, ASS... een: KMRtsukurürn.... 931

Revision of Hexactinellids with Discoctasters, with

Descriptions of Five New Species............... ID Rs: pt 48

oca NOE RR NA 61

Ueber eine in Misaki vorkommende Art von Ephelota und iiber ihre Sporenbildung, von

C. ISHIKAWA.— Die Entwickelung der Gonophoren bei Physalia maxima, von 8. Goro.

—On the Fate of the Blastopore, the Relations of the Primitive Streak, and the

Formation of the Posterior End of the Embryo in Chelonia, together with Remarks on

the Nature of Meroblastie Ova in vertebrates by K. MrrsuruRI—Living Specimen of

Pleurotomaria Beyrichii.—The Ophiuran Shoal.—Zoological Society of Tokyo.—List of

Japanese Zoologists. >

CONTENTS.

On a Mode of the Passage of the Eye ina Flat-fish......--.4- creare 1’, Nishikawa........- 73

On the Growth of the Ovarian Ovum in Chaetoguaths ................. TAB e eo 77

Votes on the Paludina-Species of Japam.sss"#;""""" "to" T.Iwakawa .......-- 83

Dendrocoryne, Inaba Vertreterinn einer neuen Familie der

y » ’

Hydromedugemee. en EE Ss GOt0u sere 77e ae 93

Ona New Species of Malacobdella (M. japonica)............- ee Snes U. Takakura .......-- 105

Notes on the Breeding Habit and Development oî Racophorus

Schlegelii, Gunther .. = ROSES: nl Tiredi» FE A 113

Miscellaneous Notes .2..:-2/--- tee Gr era ees D)... PER RE 123

Zoological Society ol Tokyo.—The New Imperial University of Kyoto.

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ANNOTATION ES

ZOOLOGICA -JAPONENSES

AUSPICIIS

SOCIETATIS ZOOLOGICÆ TOKYONENSIS

SERIATIM EDITA.

Volumen I. Pars IV.

E OB:

PUBLISHED NOVEMBRE 5, 1897.

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DEC 22 1897

Notes on an Amphioxus obtained in

Amakusa, Kyushyu,

By H, Nakagawa.

Biological Laboratory, 5th. Koto Gakko, Kumamoto.

It was in the middle of August, 1893, that I first dredged up

several specimens of Amphioxus in Gosho-no-ura, Amakusa, in the

province of Higo, Kyüshyu. Hitherto, Shika-no-shima (Shigajima) in

the province of Chikuzen was the only place where Amphioxus could be

obtained with certainty, but the number obtained there at a time is at

the best very limited. In Gosho-no-ura, the case is quite otherwise ;

fifty or even a hundred may be got in the course of five or six hours. I

have since visited the place five times, viz.—in November 1893, in April

and November, 1895, and in June and July of this year. The animals

thus obtained have been used from time to time for other purposes, but

a certain number has been employed to make the observations herein

recorded.

I. Collection.

The best time for collecting is from 9 A. M. to 3 P. M. on calm fine

days. The animals live at the depth of six to ten fathoms in coarse

shelly sand and are caught by means of a trawl.

II. Killing, Hardening and Preserving.

Picrosulphuric acid (sulphuric acid 2 parts and saturated aqueous

solution of picric acid 98 parts) has always been used for killing and

hardening. The reagent is added drop by drop to a flat-bottomed vessel

containing the animals, with sea-water just enough to cover them, until

no sign of life is shown by touching the body. Then they are put into

picrosulphuric acid alone and allowed to remain for two or three hours.

128 H. NAKAGAWA.

presently be stated. The ova and the spermatozoa, however, are not

yet fully ripe, for when these are subjected to examination the former

are not separable from one another and the latter not uniformly

developed. From these observations, it is quite.evident that the period

of active egg-laying must be between the middle of June and the end of

July. The relation of the size of the animal to its sexual maturity, I

have already stated above.

The color of the gonads is orange-red in the female and pale yellow

in the male.

V. The Number of Buccal Cirri and Branchial Arches.

The buccal cirri were counted under the microscope by cutting out

the margin of the oral aperture completely around and placing the cut-

out part under a cover glass. To make out the branchial arches, the

left side of the pharyngeal wall was dissected off and examined under the

microscope. ‘The results are given in the following table.

TABLE II.

D D | atin | Set

= the leftside. | right side. i right side.

46 … (00, 004 Gael. 21S Rei, TO MARS

371... | 23264 2408 183 CANON RER

283... | 2687... |... 1892 2 MM RE

26 … [BA NS. LOU 2 SO)

The number of the buccal cirri is thus nearly constant—1. e. 20 on

each side, but the number of the branchial arches varies, increasing with

the growth of the body, as suggested by BATESON.*

* Barrson—Materials for the Study of Variation, p, 174, foot-note.

NOTES ON AN AMPHIOXUS OBTAINED IN AMAKUSA, KYUSHYU. 129

VI. The Position of the Tail-Fin, the Number

and Distribution of Muscle-Segments, and the Formula for

the Present Species.

The number of segments was always counted only on the left side.

The segment in which the anterior end of the dorsal or ventral portion

of the tail-fin commences was counted from behind forward.

In determining the position of the atriopore I have met with no

little difficulty, but as the posterior end of the metapleural folds almost

always corresponds with the hind margin of the pore, I have taken that

end as the landmark for distinguishing the anterior and middle portions

of the three regions into which the body may be divided. For the

anterior limit of the posterior region I have taken that segment as the

first which lies just behind the projecting lip of the anus. The following

‘table shows the results of these observations.

TABLE Wye

No. of No. of No. of No. of No. of

Bod PRATI IATA ; 2 segments be- | segments be-

? È segments in |, - È

y 5 segments in Si hind the com-lhind the com-

the the mencement mencement

3 the : of the of the

anterior ‘ posterior e Al

length. I dorsal end of |ventral end of

region. middle region. region. the tail fin. | the tail fin.

Specimens possessing 66 segments in all.

PO eee! | sae CO ll... ee 17

i eerie LO nn 13... 1-27 18

Specimens possessing 65 segments in all.

483 83 2.1.2... 16 11 11 17

441 36 .. 218 10. =

413 37 Pas 11 13 18

414 37 Li... 11 12 18

40 37 Kr: 11 1] 1

39 Sta EF: 11 12 17

363 Bib iis: FAT 11 Re a

36 38 218 Si Li 17

35 37 BR < coal 12 17

33 36 i STE 12 12 18

130 H. NAKAGAWA.

No. of No. of No. of No. of No. of

segments be- | segments be-

segments in hind the com-|hind the com-

the the mencement | mencement

the of the of the

dorsal end of |ventral end of

region. middle region. region. the tail fin. | the tail fin.

Body segments in segments in

leneth. anterior posterior

Specimens possessing 64 segments in all.

TIERE Joo LTL PM ARE ee

Noe jie} tee uk’ RR a LI e GI es. 117

ABO) (AST370: 0] SH ALICIA a DIE ae, MIO MN RER

sel ey a SIT MORE Oo

| 43 … | 0870... LT) oe ee STI

43 1 | 87002, dot LT PENSION SITE la a

491... |... MST... 1e. u EPS I

01... | 2.887 NCIS ENORME Sole

QI... | vee 186 +0 | ETNA EN RE

49 … | Be. URINE

al... | 286.2 el. E

i ND Rire AAA

Al... | 288682 Er NT EMIR SIE EA IS

40%... | MSN MESS VISA

401.00] BB... 1 Ber Bla BD

404... | «ST JAMES Alles aa e e

394... | BB... JTE MR ars

39 … ese cn ROSI SSA A

88 … | et NRC RR a

1... [0086 LA. VE TIR OI

371... Le TH SP

374... er ARA

1.6 TROISE

87 … | BR NS IG balsa CO ARE

87 … 11.2386... 104. Rea

86 … RL TOO

854... LIT a

88 … | It IP ORNE

891... |. 88 sell... Re

31... |. 97 MIE... 16 ye

304... |... 36 all... OR ONE

| 08... |. STAT. MC RI RESI E RS

102... l':: 36 AT MIS RI EA

NOTES ON AN AMPHIOXUS OBTAINED IN AMAKUSA, KYUSHYU. 131

No. of No. of No. of No. of No. of

ue . co segments be- | segments be-

Body anna: segments in GET Es hind the com-lhind the com-

the the mencement | mencement

: the È of the of the

length. anterior Po shea dorsal end of |ventral end of

region. middle region. region. the tail fin. | the tail fin.

Specimens possessing 63 segments in all.

STA ee oe AR Te TI e, 17

HS El ao ant eco a Dds aot 118

dee eo poet. | ALT lg ll... 18

Eis). Sige absence LT | OS | ee

Seri Poe RL 01) 1ER El. a... 17

ee SOU el: JUG, 2. ESE le. 17

Sen ae ee ALT .: | I a nce VSS 16

Bivona LT | OME | rs

Specimens possessing 62 segments in all.

Dio | en | ET | ec: 02 OMR

Thus the dorsal origin of the tail-fin is in 28-cases out of 48 at the

dorsal end of the dorsal arm of the hindmost segment of the middle

region, and in 13 cases at the same end of the foremost segment of the

hind region, while in 6 out of the remaining 7 cases, it is 2 segments,

and in the other, 4 segments, before the anterior end of the postanal

region. The place where the anterior end of the ventral part of the

same fin commences is in 20 cases 7 segments, and in 19 cases 6 seg-

ments, before the anterior end of the hind region, whereas out of the

remaining nine cases, in five it is 8 segments, in three 5 segments, and in

one 9 segments, before the same part of the animal. From these

observations it is to be concluded that the dorsal origin of the tail-fin

is in most cases 1 segment, and its ventral end 6--7 segments, before

the hind section of the body.

By referring to Table IV it will be seen that the total number ofthe

segments composing the left side of the body varies between 62 and 66,

but in the majority of cases 64 seems to be the normal number, for that

is the case in 46 specimens out of 58. And it is also to be noted that

132 H. NAKAGAWA.

the variation is not in accordance with the size of the animal, because

one specimen of only 105 mm. in length possessed 64 segments, while

another of 513 mm. had only 62.

As to the distribution of the segments into the three regions, it will

perhaps be proper to seek its normal state among the specimens that

possess the average number of segments. So by consulting the third

section of T'abie IV the two cases, 36, 17, 11 and 37, 17, 10, are ap-

parently most predominant, the former occurring 16 times and the latter

11 times among 36 cases. Hence the formula for the present species is

36 (37), 17, 11 (10)—64, 35.

This does not apply to any of the nine species mentioned in E. A.

ANDREWS’ paper*, but as I have at present no opportunity of examining

the specimens belonging to the species given there, I can not say

whether we have here a new species or whether it belongs to one of the

nine, which has not been collected and examined in sufficient number.

August 17, 1897.

Printed September 15, 1897.

* An Amphioxus from Japan, Zool. Anz., No. 468.

On a New Species of Elasipoda from

Misaki.

By Prof. K. Mitsukuri.

Science, College Imp. Univ. Tokyo.

Ilyodemon Ijimai, sp. n.

This is by far the commonest of the holothurians found in the

deeper parts of the seas about the Misaki Marine Station, exceeding

greatly in number Letmogone violacea, Théel which is next to itin

abundance.

The definition of the genus Ilyodemon given by THEEL* is as follows :—

Tentacles fifteen, rather large and non-retractile. The lateral

ambulacra of the ventral surface with large pedicels, apparently

disposed in a double row all along each side of that surface. "The

odd ambulacrum naked. The dorsal surface with a crowded

series of very numerous, retractile, slender, rather long processes,

disposed in three or four irregular, close-set rows all along

each of its ambulacra. Integument with numerous wheels and

dichotomously branched bodies.

The present species falls in well with this ‘definition, excepting a

single point. Its calcareous deposits wholly lack dichotomously branched

bodies. The specimens in my possession are quite numerous, and not

only do I fail to discover any dichotomously branched bodies in all the

preparations which show other kinds of calcareous deposits beautifully;

but there is not in any specimen any trace of larger and smaller white

spots visible to the naked eye, which are stated by THEEL to be present

in I. maculatus, andto be caused by those bodies. In view of this fact, it

* Report on the Scientific Results of the Exploring Voyage of H.M.S. Challenger

1873-76, vol, IV, p. 84. |

134 K. MITSUKURI.

would be necessary to modify the last part of the generic definition as

follows: “Integument with numerous wheels, sometimes also with

dichotomously branched bodies.”

The same point also separates off the present species at once from

I. maculatus, Théel, the only species, so far as I can discover, known

hitherto of the genus.

The main features of the species are as follows :—

Body elongated, of almost equal breadth throughout, being in

largest alcoholic specimens 120-160 mm. long and 35-40 mm. wide, about

3-4 times as long as broad. Mouth anterior, subventral. Anus

posterior, subdorsal. Tentacles fifteen, with large circular discoidal

ends ; on the whole, the ventral tentacles smaller than the dorsal. The

odd ventral ambulacrum naked. Pedicels of each lateral ambulacrum

22-25, the alternate arrangement of pedicels in the inner and outer rows

of each amlulacrun very obvious in some specimens, and. hardly

recognizable in others, the difference being probably due to the degree

of contraction in alcoholic specimens. Processes of each of the dorsal

amlulacra very numerous, conical, rather short, the longest about

one-third of the width of the body,in about four rows, of which the

inner two are sometimes distinctly separated by a space from the outer

two. Back naked in the median dorsal interamlulacrum, with the

exception of the genital process in the anterior part. Integument soft,

sometimes thin, sometimes thicker and spongy (the difference being

probably due to the state of preservation), more or less translucent, most

so in fresh state, internal organs (especially light-colored organs like the

generative organs) being visible from the surface. Calcareous deposits

of two kinds; large wheels with six central rods and small wheels

mostly with four central rods. Among the former, the largest are about

0.21 mm. in diameter and have about nine spokes | (See THEEL, loc. cit.

pl. XXXVI, fig. 15). These grade off into.those about 0.1 mm. in diameter

and with about twelve spokes. Various stages of growth in the large

wheels are visible, as given by Tuten. The small wheels (See THEEL

loc. cit. pl. XXXVI, fig. 17) are 0.046-0.059 mm. in diameter. In them

A NEW SPECIES OF ELASTPODA. 135

the felly is narrower and the spokes (usually 12) are shorter. Large

wheels are most numerous on the dorsal surface, and in the lateral

pedicels. Small wheels are predominant in the ventral perisoma and in

the dorsal papille. Arcuate or spindle-shaped spicules are present on

the pedicels and tentacles.

Color.—In alcohol, white grey without any white spots. In fresh

state, beautiful light violet with deeper tints on the dorsal papille, etc.

A rather broad straw yellow streak on each side of the dorsal surface

along and ontside the outer series of dorsal papille, becoming fainter

toward the front.

Habitat.—In all parts of the Sagami Bay and of the outer part of

the Tokyo Bay in waters deeper than 250 fathoms. Specimens in

the Museum of this Institute.

The above description shows that this species closely resembles I.

maculatus, the only distinct points of difference being the entire absence

of dichotomously branched bodies, and the comparative shortness of the

dorsal papille. Compared with the measurements given by THEEL,

the wheels, large and small, seem also to be slightly larger in the

present species. It is a fact worth noting that the two species of

Ilyodemon occur at about the same longitudes (between 120°—150° E)

but are separated by about 20 degrees of latitude. Anatomical notes as

well as some interesting facts relative to the growth of the animal I

reserve for some future occasion.

I take great pleasure in naming this present species after my

friend and colleague, Prof. Dr. Ista, in pleasant remembrance of many

uncomfortable but fruitful days spent together on fishing boats on the

Sagami seas and in appreciation of his great services in unearthing the

treasures of those deeper parts.

Sept. 19, 1897.

Printed October 15, 1897.

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Preliminary Note on the Development of the

Pronephros in Petromyzon.

By S. Hatta.

Biological Laboratory, Nobles’ School, Tokyo.

I have recently studied the history of development of the pronephros

in Petromyzon, and the results arrived at throw, I believe, some light

on this subject. I will enumerate the chief points obtained in the

following pages.

1). Im Petromyzon, the pronephros becomes apparent at a com-

paratively early stage, that is, the stage approximately corresponding to

the early section of stage II in the list given by me*. When the

metameric segmentation of the mesoblast in the anterier region of the

body has been finished, we can distinguish, in each of a few somites in

this part, a piece of mesoblast which les between the proximal somatic

and the distal unsegmented portion (the lateral plate). The component

cells of this piece first assume the regular arrangement of a columnar

epithelium, and the parietal row of them is a little elevated aganist

the epiblast. It is this piece which develops, as the subsequent history

teaches, into the pronephric tubules and the nephrostomes; I will,

therefore, hereafter call it the anlage of the pronephros. All the anlagen

of the pronephros are cut off, with the lateral plates, from the segmented

portion of the mesoblast, and are still more thickened by the repeated

multiplication of cells. These thickened parts, however, is never a solid

knob; for they acquire a lumen as soon as the anlagen come into view.

The lumina of the pronephric anlagen communicate, of course, with the

body cavity, which is a mere fissure in the stage in question. The cells

ge the the anlagen are high and columnar in shape, while the cells

* Harra, S.—Contrib. to the Morph. of Cyclostom. I. On the Formation of the Heart

in Petromyzon. Journ. Coll. Sci., Imp: Univ. l'okyo, vol. X, pt, II

138 Ss. HATTA.

of both the somatic and splanchnic layers of the lateral mesoblast

are of irregularly quadratic forms.

2). The first appearance of the anlage of the pronephros is observed

in the region under the fourth somite ; this is the first pair of pronephric

tubules. The following pairs become pronounced one after the other.

The distal end of these tubules become confluent by the multiplication

of their cells and thus a direct connection is established among them.

These connecting pieces together from the collecting duct (Sammelrohr

of RUcKERT or the anterior continuation of the segmental duct) of

the pronephros.

3). When all the tubules have become developed, there are 6 pairs,

the first of which contains no lumen, while all the remaining pairs soon

acquire a tubular structure. The independent canalization of each

tubule proceeds backwards and into the collecting ducts, and finally

all the tubules and the duct on each side are set in free communication.

Then the ducts shift toward the median line of the body ; consequently

each tubule takes a latero-ventral course, and the funnels themselves be-

come open just ventrally.

4). The first pair of tubules does not develop further, and the second

pair degenerates after a short existence, while the 6th. pair loses its

connection with the duct. The disconnected tubules remain unchanged

for some time, but finally they disappear.

D) The total number of persistent tubules is, threfore, six, i. e. three

pairs, of which the second and third pairs are developed most vigorously.

This fact would explain why certain investigators believe 3 pairs to be

present, while we are told by some others that there exist 4 or 5 pairs.

In later stages, the foremost pair of the three persistent tubules is in

close contact with the posterior wall of the gill-chamber.

6). The tubules are prolonged and grow downwards, pushing their

way into the body-cavity, until the funnels almost meet with the cardiac

tube. The proximal portion of the tubules also grows enormously and

becomes coiled many times, so that the chest-cavity is at last filled up

with the convolutions of the tubules and the cardiac tube.

PRONEPHROS IN PETROMYZON. 139

7). In the anterior region, the segmental duct has every appearance

of having been formed in the same manner by the thickenirig of the

proximal margin of the lateral plates, as in the pronephros proper ; the

only difference is that the anlagen do not develop into tubules, but

unite with each other to form the duct. Owing to a large quantity of

yolkmass in the posterior region the process is here much delayed and

somewhat modified: it is brought about by the multiplication of a few

cells proliferated from the proximal margin of the somatic layer of the

lateral plates. I have observed neither any trace of an epiblastic origin

of the duct nor any free growth of its posterior end*. In a much later

stage, the posterior extremities of the ducts open into the cloacal section

of the enteric canal.

8). From early stages, there is a complete blood supply in the pro-

nephros: the arterial blood comes from the dorsal aorta; the

blood corpuscles are found scattered between the tubules, and are

afterwards transformed into two pairs of glomi, the anterior of which

soon atrophies. The venous blood is taken away by the cardinal veins

which drain the pronephros from early stages.

From the facts mentioned above the following conclusions are

justified : Both the pronephric tubules and the segmental ducts are

purely organs of the lateral unsegemented portion of the mesoblast +;

the somatic mesoblast as well as the other germinal layers have no

share in their formation. The anlagen of the tubules follow, from

their first appearance, the same segmental arrangement as the

mesoblastic somites. The maximum number of the pronephric tubules

formed is 6 pairs, of which the first, second, and sixth degenerate one

after the other. The persistent tubules are, therefore, the third, fourth,

and fifth, of which the third pair is not so well developed as the next

* ] have observed a case in which mitotic cell divisions are taking place in that point

of the epiblast, where the segmental duct lies in close contact with it; this subject will be

explained in the full paper.

+ For convenience’s sake I divide the mesoblast into two portions the somatic and

the lateral plates, and no more.

140 S. HATTA.

two. Itis an interesting fact that the first and second pairs originate

in the region where afterwards the gill-slits are formed, and they

disappear when the latter come into view. In later stages, the third or

foremost pair of persistent tubules is in close contact with the hind wall

of the gill-chamber.

These facts bear a close resemblance with those in Bdellostoma as

described quite recently by G.C. Price*. Hence we have a strong

reason to believe that the pronephros of cyclostomata is homologous

’

with the “ Nierencanälchen” of Amphioxus as described by TH.

Bovertt, and that at the same time, the persistent tubules of

Petromyzon are homologous with those of Selachia, Teleostei, Amphibia,

&c. ; the mesonephros does not seem to be a part of the pronephros,

but it probably belongs to another ‘series of excretory organs.

The full paper will appear in the next number of the Journal of the

College of Science, Imp: Univ., Tokyo.

June 12, 1897.

* Price.—Development of the Excretory Organs of a Myxinoid, Bdellostoma

Stouti, Lockington. Zool. Jahrb., Bd. X.

+ Boveri, Tu.—Die Nierencanilchen des Amphioxus. Zool. Jahrb., Bd. V.

Printed October 15, 1897.

Sur une nouvelle espèce japonaise du genre

Lucernaria.

Par A. Oka.

Laboratoire zoologique de l’école normale supérieure, Tokio.

Au cours de recherches zoologiques sur les côtes de la province de

Nagato, l’an dernier, j'ai eu la bonne fortune de pouvoir recueillir une

méduse appartenant au genre singulier des Lucernarie dont aucun

représentant n’a figuré jusqu'à ici dans la faune japonaise. Je n'en ai

rencontré qu’un exemplaire, mais cet unique spécimen est interessant non

seulement par sa nouveauté dans notre pays mais encore par sa forme qui

diffère plus ou moins nettement de celle de toutes les autres espèces du

même genre. C'est pour cette double raison que j'ai cru utile d’en

donner une courte description.

Description.—Comme chez toutes les autres Lucernarie, le corps

de cette méduse se compose de deux parties bien distinctes, le calice et

la tige.

La tige, de forme cylindrique, courte, mesure 4

mm. de long et 2 mm. de diamètre. Le bout inférieur,

qui est un peu dilaté, fonctionne comme une ventouse

au moyen de laquelle l’animal se fixe.

Le calice, qui est la plus importante partie du

corps, n’est aucunement cyathiforme comme on le

trouve généralement chez les méduses de la famille

Fie. 1. des Lucernariidæ. Au contraire, il représente une

croix grecque mince dont les bras sont divisés en deux à l'extrémité.

On y distingue deux surfaces, une orale et une aborale, correspondant

respectivement à la face interne et externe de la coupe. C'est au centre

de la face aborale que le calice se joint à la tige.

142 AMORE

Au milieu de la surface orale il y a un tube, assez court, le ma-

nubriam, à l'extrémité duquel s'ouvre la bouche. En coupe transversale

ce tube est plus ou moins carré. L'extrémité libre en est quelque peu

dilatée, la lèvre de la bonche montre beaucoup de plis gardant tonjours

un contour plus ou moins quadrangulaire.

Les bras de la croix sont lisses à la face aborale, où l’on ne trouve

qu'une légère ondulation de la peau causée par la contraction des muscles

situés directement au dessous. La surface orale, au contraire, présente

deux élévations longitudinales s'étendant presque jusqu’au bout et

separées l’une de l’autre par un sillon assez profond, d’où il resulte

qu’en coupe transversale chaque bras donne le contour d’un B couché.

Près du centre de la croix, là, où

les sillons atteignent les parois du

manubrium,—car les angles de ce tube

prismatique se trouve chacun en face

de l'espace entre deux bras —il devien-

Fic. 2. nent brusquement beaucoup plus pro-

fonds pour former ce qu’on appelle l’entonnoir septal. La, les élévations

que je viens de mentionner paraissent se toucher, formant chacune au

point de jonction un angle droit avec son analogue du bras adjacent.

Comme je l’ai déjà signalé chaque bras se divise à l'extrémité en

deux branches dont le bout distal est fourni d’une touffe de processus

tentaculaires. Ces appendices, qui servent sans doute d’organe de

succion quand le sujet cherche sa nourriture, sont chez notre exemplaire

au nombre de 24 par touffe. Cette méduse possédant en tout huit touffes

prreilles le nombre total de ses tentacules se monte à 192.

Le calice, étendu à plat, mesure 29 mm. de diamètre, chaque bras

étant de 11 mm. de long sur 3 mm. de large. La portion où le bras est

divisé en deux branches mesure environs 3,5 mm. Placé dans l'alcool

le corps de cette méduse se réduit presqu’ aux trois quarts de sa grandeur

originale. Les bras se contractent plus que le reste. Ils se conrbent

en même temps en dedans et donnent alors à l'animal l'aspect

caractéristique d’une Lucernaria. Quand il vivait, cependant, les bras

NOUVELLE ESPECE DE LUCERNARIA. 143

étaient si minces et si mous qu'on aurait pu les prendre à première vue

pour des vers némertiniens,

Notre exemplaire qui se trouvait attaché sur une feuille de Zostera

marina était, en état de vie, d'une couleur verte foncée imitant

parfaitement celle de la plante. Je regrette bien de n’avoir pas déterminé

d’où vient cette couleur qui disparait tres vite dans l'alcool. Grâce a

cette ressemblance parfait: de couleur ce ne fut que par hasard que

l’animal fut découvert, ce fait explique sans doute pourquoi il a échappé

jusqu’à alors notre attention. |

Habitat —L’animal que je viens de décrire ci-dessus provient de

Kogushi, petite ville de la côte occidentale de la province de Nagato, où

je l’ai recueilli dans un dragage fait par 6-8 mètres de profondeur le 3

avril 1896.

Anatomie.—Pour étudier la structure interne de cette méduse j'en

ai disséqué la tige et un bras.

La cavité cœlentérique, qui est continue partout, s'étend jusqu’ au

bout des bras. Dans chaque bras il ya un septum longitudinal qui

divise cette cavité en deux moitiés latérales. La séparation, cependant,

n’est pas complète, car à la base de la portion branchée se trouve au

septum une petite ouverture par laquelle les cavités des deux cotés

viennent à communiquer l’une avec l’autre.

Les glandes génitales forment huit rubans de contour irrégulier.

Chaque ruban est composé d’un grand nombre de vésicules séparées,

attachées en rang au plafond de la cavité du bras. Ce sont des glandes

génitales qui causent les huit élévations que nous avons observées dans

notre description de la surface externe du calice.

Les coupes minces montrent que la paroi du corps se compose de

trois feuilles, l’ectoderme, l’endoderme et la membrane supportante.

L’ectoderme couvre toute la surface externe du corps. L’endoderme

revêt partout la cavité cœlentérique. La membrane supportante,

gélatineuse et transparente, se rencontre entre les deux couches a

toutes les parties du corps. Même la paroi des tentacules au bout des

bras montre très nettement ces trois feuilles. Comme le représente la

144 A. OKA.

figure 3 Jes ‘glandes :gemitales sont situées entre l’endoderme.et la

membrane supportante.

La cavité du corps se

prolonge jusqu'à la tige.

Celle-ci est en somme

uniloculaire, bien qu’à la

périphérie sa cavité soit

divisée en quatre parties par

les quatre élévations très

remarquables qui s'étendent

du calice au bout inferieur

de la tige. La figure 4 re-

présentant une coupe trans-

versale de la tige indique

non seulement la forme. de

ces élévations mais encore

l'étendue de la cavitéinterne.

Les fibres musculaires, qui se trouvent toujours

dans la substance de la membrane supportante, se

groupent en huit rubans s'étendant entre deux touffes

successives de tentacules. Comme on doit le supposer

Fie. 4. d'après la configuration de la croix, ces rubans

musculaires ne sont pas du tout d’egale longueur ; ceux qui joignent les

touffes au bout du même bras sont très courts, tandisque ceux qui s’

étendent entre les bouts des deux bras sont naturellement beaucoup plus

longs.

Il ya en outre un système de quatre rubans musculaires situés dans

les septa longitudinaux des bras. Leur contraction courbe évidemment

les bras en dedans, ce que l’on voit se produire subitement quand on

jette l'animal vivant dans J'alcool.

À l'égard de l'orientation du corps de cette méduse nous somme

portés, par comparaison avec des autres Lucernariæ, aux conclusions

suivantes :

NOUVELLE ESPECE DE LUCERNARIA. 145

1. Les rayons sur lesquels se trouvent les septa sont Interradii, la

petite ouverture dans les septa représentant le canal marginal des

Acalephæ. 2. Les touffes de tentacules, ainsi que les glandes génitales

sont, par conséquent, sur les Adradii. La forme en croix que présente

le calice de cette méduse ne vient d’autre chose que de la suppression du

développement sur les Perradii.

Remarques.—J’ai cherché vainement dans la littérature, dont je

dispose, une forme qui serait identique à la nôtre. Il est donc fort

probable qu'elle représente une espèce encore inédite. Toutefois, n’ayant

pas pu consulter tous les mémoires publiés sur ce sujet, je n’insisterai

pas sur ce point. Mais sila méduse que je viens de décrire se trouvait

etre nouvelle, je crois que le mieux serait de la designer sous le nom

de Lucernaria nagatensis.

Le nom japonais que je propose pour cette meduse est celui de

Jumonji-kuragé (Jumonji, croix; kurage, meduse: méduse cruciforme).

Comme on le sait l'ordre des Stauromédusæ se divise en deux fa-

milles, Lucernariide et Tesseride. J’ai signalé ci-dessus l’existence

sur nos còtes d’une espèce au moins de la première famille. Quant è la

seconde, on connait déjà aussi une forme japonaise, dont le spécimen,

également unique, a été recueilli il y a un peu plus de trois ans par mon

collègue M. M. INAB4A On en trouve la description par M. K.

KISHINOUYE, sous le nom de Depastrum Inabai, dans le numéro 61 du

Zoological Magazine.

Le 10 oct. 1897.

Imprimé le 25 octobre 1897.

P À

1163 x nr

æ da | ì

| : re en u one na

| | jot hen sof sas dI a

4 4

Ji f judd nize RARE

fi : x { [ar Z [ ul » be. 44 dr nea

È ;

;

Sur une nouvelle espèce japonaise du genre

Phoronis.

Par A. Oka.

Laboratoire zoologique de l’école normale supérieure, Tokio.

Grâce à l’amabilité de M. le Prof. I. IsımA de l'Université j'ai pu

examiner récemment une espèce indigène du genre Phoronis.

Nous connaissions depuis longtemps quelques formes larvales nom-

mées Actinotrocha. Nous étions accoutumés à en rencontrer un grand

nombre parmi les Planktons de nos côtes et il nous paraissait toujours

inexplicable que l'animal adulte ne se montrât nulle part. Or, le

savant zoologiste en a découvert, il y a un an, une colonie assez grande,

composée de plusieurs centaines d'individus. C’est de cette colonie que

proviennent les spécimens que je vais décrire ci-dessous. Chose étrange,

on n'a, jusqu'au moment où j'écris, pas retrouvé cet animal.

On sait que la Phoronis habite la mer et que chaque individu de ce

genre s’y construit comme demeure un long tube. Chez notre espèce

ce tube est formé de matières chitineuses sécrétées par la peau de

l'animal. La paroi en est très mince, hyaline, d'une couleur jaune très

pale; la surface est souillée d’une boue qui semble être faite des

excrétions mêmes de l'animal. On n’y trouve jamais de sable.

Ces tubes qui sont 1 mm. de large, mais dont je n'ai pu déterminer

la longueur, s’entrelacent formant un véritable feutre. L’épaisseur de

ce dernier peut être de plus 40 mm. Un petit ascidien s’y trouvait

complètement caché. Au centre de la colonie on compte de 10 à 15

individus sur 10 mm. carré.

Chez nos exemplaires, conservés dans l’alcool, le corps mesure, y

compris la couronne tentaculaire, plus de 40 mm. de long et 0.5 mm. de

large. A l'état vivant, il était, sans doute, plus grand. Au sujet de

148 AL NORA,

la forme du corps proprement dit, ainsi que de la couronne, j'ai

trouvé qu'elle ne fat en rien différente de celle du Phoronis psammophila

décrit par M. I. Corı.*

Le nombre de tentacules était chez trois individus pris au hasard,

de 1 176, 138; soit d’environ 150 en moyénné. Les tentacules

mesurent elles-mêmes 2 mm. de Jong.

La colonie a été recueillie, ainsi que me l’a communiqué M. le Prof.

Isıma, au mois d'août de l’année dernière, dans un dragage fait

en rade de Moroiso, près de Misaki où se trouve notre station

zoologique.

Nous ne connaissons à présent que sept. espèces distinctes. de

Phoronis :

1. Ph. hippocrepia, Wright.

2.. Ph. australis, Haswell.

3. «Ph. Buski, McIntosh. i si

4. . Ph. Kowalevskyi, Caldwell. nia irta

5. Ph. psammophila, Cori.

6... Ph. architecta, Andrews.

7. Ph.Sabatieri, Roule. |

Les quatre espèces européennes, savoir. Ph. hippocrepia, Ph.

Kowalevskyi, Ph. psammophila, et Ph. Sabatieri, ainsi que: l'espèce

américaine, Ph, architecta, se distinguent très aisément de notre espèce

en ce qu'elles ne possèdent que la moitié des tentacules qu’a cette

dernière. D'autre part, Ph. Buski, est fournie d'environ 300 tentacules,

c'est presque le double du nombre de notre espèce.’ Quant à la Phoronis

australis il n'est ‘pas besoin’de:la cormparer avec: la: nôtre; car ses

tentacules mesurant plus de 6 fois la longueur de celles:de cette-dernièré

n'ont pas leurs pareilles parmi les espèces Jusqu'ici-décrites. +, : “>

= Notre animal ne répond donc à .aneune:des espèces:connues:et.]e

crois être autorisé à en faire une nouvelle espèce;Ph:.Ijénai. 7 ur!

‘4 Cont, C.J.— Untersichungen über die Anatomie ind Histölogie der’ Gattung

Phoronis: Zeitsehr. f. wiss. Zool., LI. rela sinon ag

TENTE

| Imprimé le 25.octobre 1894; uw davo. Ë Yet

Miscellaneous Notes.

The Occurrence of Sphærothuria bitentaculata, Ludwig in the

Sagami Seas.—This curious and interesting holothurian, looking

externally like some simple Ascidian was obtained in the séas near the

Galapagos Islands by Prof. ALEXANDER AGasstz,while on the exploring

expedition to those parts on the U. S. Fish Conimission steamer “ Alba-

tross,” and was described by Lupwie in his report on the’ Holothurioidea

of the Expedition (Mem. Mus. Comp. Zoöl., vol. XVII, no. 3) under

the name given above.‘ During the summer just past, I have been

fortunate enough to obtain two specimens of this species in the seas near

the Misaki Marine Station: One specitnen was obtained about seven

miles south of Misaki in what is known as the Uraga Channel at the

depth of about 350 fathoms: The other was fished up about five miles

west of Misaki in the Sagaini Bay at about the same'depth. Both were

caught by a fishing long line and found attached to the jelly-mass

which Bdellostoma secretes and hides itself in. The specimens on the

whole tally well with'the descriptions of Lupwic. The occurrence of

this rare species at two places separated from each other by the entire

width of the Pacific is, to say the least, very interesting and goes once

thore to establish the comparative uniformity of the deep-sea fauna. The

discovery ‘ofthe animal at intermediate stations would not now be

surprising atall >” K. MITSUKURI.

Contributions to the Morphology of Cyclostomata. I. On the

Formation of the-Heart in Petromyzon, by S. Hatta. Jour. Sci. Coll.,

Imp. Univ: Tokio, Vol. X, Pt, II, p. 225-237. PL .XVIII— Die erste

Andeutung des "Herzens findet man schon an sehr jungen Embryonen

welche noch’ eine: wenige Zahl der Mesodermsegmente und nur: zwei

Paar Kiemeheinbuchtungen besitzen. In diesem Stadium beobachten

wir immer, zwischen den zwei primaren Keimschichten zerstreut, eine

Anzahl Zellen, die den Mesodermzellen ganz ähnlich aussehen. Dieselbe

gruppiren sich besonders auf der Medianlinie des Bodens, vor jener Stelle,

wo der weit ausgedehnte Mitteldarm sich mit dem schlanken Vorderdarm

verbindet. Diese mesenchymatischen Zellen weichen nach emiger Zeit

auseinander: und bilden: ein Rohr, indem’sie sich’ epithelial anordnen.

Dieses ‘Gebilde welches unterdessen rechts und links von den beiden

150

visceralen Seitenplatten umschlossen wird, ist nichts anderes als das.

Herzendothel, wahrend die letzeren die Anlage des Perikardiums.

darstellen. Das Herz hat nun, also, die Gestalt eines langen Epithelrohrs,.

welches von den mesenterialen Visceralhäuten an der Körper- und Darm-

wand suspendirt wird. Diese Suspensorien (Mesocardium anterius-

et M. posterius) erfahren, aber, kurz nachher eine Rückbildung, so dass

das Herzrohr schliesslich frei zu hangen kommt. Im nächsten Stadium.

schnurt sich das Herzrohr, gleichwie die Perikardialhaut, in ihrer Mitte:

ein und wird in zwei konischen Halften geteilt, von denen die vordere-

das Ventrikel und die hintere das Atrium darstellt.

Das Herzendothel bildet sich also nicht etwa durch die Delamina-

tion der visceralen Seitenplatten, wie A. SHIPLEY annimmt, sondern es

verdankt seinen Ursprung einzig und allein jenen im ventralen Raume

vor dem Mitteldarm befindlichen Mesenchymzellen. Was die Herkunft

dieser Zellen, worüber die Ansichten der tüchtigen Embryologen aus-

einander gehen, betrifft, so kann ich unglücklicherweise nichts bestimmtes.

aussagen ; da aber mehrere Mesodermzellen von den ventralen Kanten

der Seitenplatten hinabfallen, bin ich geneigt anzunehmen, dass sich diese:

freigewordenen Zellen in jenem Raume zusammen gruppirt haben. Nach

der Angabe A. SHIPLEY’s tragen diese Zellen zur weiteren Bildung der

Seitenplatten bei, wie ich sie auch schon in meiner früheren Arbeit.

bestätigt habe. Da in späteren Entwicklungsstadien, aber, mehrere:

mitotischen Figuren im eigentlichen Mesoderm selbst zu beobachten

sind, scheinen die ventralen Partien des Mesoderms einzig und allein

durch das Wachstum der Seitenplatten vervollkommnet zu werden, so:

dass die Zellen einer anderen Herkunft mit derselben nichts zu tun

haben. S. HATTA.

Zoological Society of Tokyo.—The monthly meeting of the Society

for September was held in the lecture room of the Zoological Institute

of the College of Science, Imp. Univ., at 2° P.M. Saturday the 18th.

The first part of the meeting was occupied with the election of officers.

for the ensuing year. The following gentlemen were elected:

President. Prof. I. Isıma.

Secretary. Mr. T. Arba.

Librarian. Mr. S. IKEDA.

Treasurer. Mr. M. NAMIYE.

Prof. MirsUKURI then read a paper “On the Occurrence of Sphero-.

thuria bitentaculata, Ludw. and Ilyodaemon Ijimai, sp. n: in the Sea.of

151

Sagami.” The substance of the paper is found elsewhere in the present

issue.

Personal News.

Mr. Jıuta Hara has been appointed Professor of Zoology in the

Agricultural College of Sapporo. His address hereafter will be Agricul-

tural College, Sapporo, Hokkaido.

Dr. ASsAJIRO OKA has removed as Professor of Zoology to the

Higher Normal Schoolof Tokyo. His place in Yamaguchi has been

taken by Mr. MASAMARU INABA, hitberto in Mayebashi.

Prof. MirsuKURI has been “delegated by the Imperial Government

to the Seal Conference in Washington. After the Conference he will

spend some months elsewhere in America and in Europe.

1:52

“ist of Publications received in exchange for the Annotationes until October,

1897, arranged alphabetically according to Authors or Societies.

Auus, E. Ph.—The Cranial Muscles and Cranial and First Spinal Nerves in Amia

1, calva. A, ’ i ?

Carnoy, JB? et LeBRUN, H.-—La fécondation chez l’Ascaris mégalocephala.

Deutschen Gesellschaft für Natur- u. Völkerkunde Ostasiens, Mitteilungen der.

2 ‘Hfte. 1,,5, 9, 10, 11, 13, 46, 48, 49, 52, 59. _

Dvurrpen. J. E.—The Actinarian Family Aliciide.

Harrraus, Cl.—Beitriige zur Meeresfauna von Helgoland. X. Die Hydromedusen

Jatnaica, Journal of the Institute of. «Vol. II, No. 4.’

Manchester Microscopical Society, Transactions and Annual Report ete. of, for

1896.

Naturhist. Forening i Kjobenhavn, Videnskabelige Meddelelser fra den, for 1896.

Natuurkundig Tijdschrift voor Nederlandsch Indie. Deel LVI. Neg. Ser. Deel V.

Ditto, Alphabetisch Register van, op Deel I-XXX & Deel XXXI—L.

, Naamregister van, op Deel I-XXX.

Nebraska, Calender of the Univ. of, for 1896-97.

North Carolina, Catalogue of the Univ. of, for 1896-97. |

Novitates Zoologice. Vol. IV. Nos. 1 & 2.

Società Romana per i Studi zoologici, Bolletino della. Vol. VI, fase. I e II.

Smithsonian Institution, Publications of. May, 1896.

SPENGEL, J. W.—Bemerkungen zum Aufsatz von N. Nassanow über die Exkre-

tionsorgane der Ascariden in No. 538 des Zoolog. Anzeigers. r

Wiupeman, E. de. —Prodrome de la Flore algologique des Indes Néerlandaises.

List of Names to which the Annotationes are regularly sent.

AFRICA. Josephs-Universität.

Cape Town. Budapest.

South African Museum. Zoolog. u. vergleich-anatomisches

Institut.

ARGENTINE REPUBLIC. È

Zoolog. Institut d. Kgl. Ungar.-

Buenos Ayres. }

Josephs- Polytechnikum.

Sociedad Cientifica Argentina. i

Czernowitz.

Ausrria-Huneary. Zoolog. Institut der Universität.

Agram. Graz. i

National-Museum der Kgl. Franz- Zoolog.-Zootomisches Institut.

Innsbruck.

Zoolog. Institut.

Klausenburg.

Medic.-naturwiss. Gesellschaft.

Zoolog. Institut d. K. Franz-

Josephs-Univ.

Krakau.

K. k. Akademie d. Wissenschaften.

Zoolog. Institut.

Lemberg.

Zoolog. Museum.

Prag.

Zoolog. Institut.

Böhmische Gesellschaft d. Wis-

senschaften.

Wien,

K. k. Akademie d. Wissenschaften.

K. k. Zoolog.-botan. Gesellschaft.

Zoolog.-vergleich.-anatom. Institut.

Zoolog. Abteilung d. k. k. natur- ‘

hist. Hofmuseums.

AUSTRALIA.

Melbourne, Victoria.

Univ. of Melbourne.

Sydney, New South Wales.

Univ. of Sydney.

Linnean Soc. of N. S. W.

BeLGIUM.

Bruwelles.

Musée royal d’hist. natur. de Bel-

gique.

Société royale

Bruxelles.

Linnéenne de

Gand.

Musée zoolog.

Liege.

Institut zoolog.

Louvain.

Cellule, Redaction de Ja, Chez M.

le Prof. Carnoy. -

Institut zoolog.

153

BRAZIL.

Rio de Janeiro.

Museu nacional.

Sao Paulo.

Museu Paulista.

Bririsx INDIA.

Bombay.

Univ. of Bombay.

Calcutta.

Medical College.

Madras.

Univ. of Madras.

CANADA.

Montreal.

McGill College.

Toronto.

Univ. of Toronto.

CHILI.

Santiago.

Deutscher wissensch. Verein.

Societe scientifique du Chili.

CHINA.

Shanghai.

Musée de Zikawei, pres Shanghai.

DENMARK.

Kjöbenharn.

Naturhistorisk Forening.

Zoolog. Museum.

DEUTSCHLAND.

Vide GERMANY.

ENGLAND.

Vide Great BrItAIN & IRELAND.

FRANCE.

Bordeaux.

Société linnéenne.

154

Caen.

Soc. linnéenne de Normandie.

Clermont-Ferrand.

Faculté des sciences.

Grenoble.

Soc.

natur. et des arts industriélles d.

de statistique des sciences

départ. de l’Isere.

Lille.

Laboratoire de Zoologie.

Lyons.

Association des amis d. sc. natur.

Marseilles.

Académie des sciences, belles lettres

et arts.

Montpellier.

Académie des sciences et lettres.

Menton.

Azris, Laboratoire de M. E. Pa.

Nancy.

Laboratoire zoolog. de la Faculté

d. sciences.

Nantes.

Soc. d. se. natur. de l’ouest de la

France.

Paris.

Institut Pasteur.

Laboratoire d’histologie de la

Faculté de Medieine.

Laboratoire de zoologie de la

Faculté des sciences.

Muséum d’historie naturelle.

S. Altesse serenissime Prince de

Monaco.

Soc. de Biologie.

Soc. zoolog. de France.

Rouen.

Soc. des sc. naturelles.

Toulouse.

Soc. de Vhistoire naturelle.

GERMANY.

Berlin.

Anatom. Institut, LI.

Kg]. Akademie der Wissenschaften.

Zoolog. Institut.

Bonn.

Anatom. Institut.

Naturhist. Verein d. preus. Rhein-

lande, Westfalens u. d. Regie-

rungsbezirks Osnabriick.

Zoolog. u. vergl.-anatom. Institut.

Braunschweig.

Naturwissenschaftl. Rundschau,

Redaktion der.

Breslau.

Anatom. Institut.

Zoolog. Institut.

Dresden.

Kgl. zoolog. u. anthrop.-ethnogr.

Museum.

Erlangen.

Biologisches Centralblatt, Redak-

tion bei Herrn Prof. Dr. Rosen-

thal.

Zoolog. Institut.

Frankfurt am Main.

Senckenberg.. Institut u. Museum.

Freiburg, à Br.

Anatom. Institut.

Zoolog. Institut.

Giessen.

Anatom. Institut.

Deutsche zoolog. Gesellschaft bei

Herrn Prof Dr. J. W. Spengel.

Zoolog. u. vergl.-anatom. Institut.

Göttingen.

Anatom. Institut.

Zeitschr. f. wiss. Mikroskopie, Re-

daktion bei Herrn Prof. Dr. W.

J. Behrens.

Zoolog.-zootom. Institut.

‘Greifswald.

Anatom. Institut.

Zoolog. Institut.

‚Halle a. S.

‘Anatom. Institut.

Zoolog. Institut.

‚Hamburg.

Naturhist. Museum.

‚Hannover.

Naturhist. Gesellschaft.

‚Heidelbery.

Anatom. Institut.

Zoolog. Institut.

Zoolog. Centralblatt, Redaktion

bei Herrn Dr. A. Schuberg.

‚Helgoland.

Kgl. Biolog. Anstalt.

‚Jena.

Anatom. Institut.

Anatom. Anzeiger, Redaktion bei

Herrn Prof. Dr. Karl v. Bardele-

ben.

Zoolog. Institut.

‚Karlsruhe.

Naturwiss. Verein.

Kiel.

“ Anatom. Institut.

Zoolog. Institut.

Königsberg.

Anatom. Institut.

Zoolog. Institut.

Leipzig.

Anatom. Institut.

Carus, Herr Prof. Dr. J. V.

Kgl. Sächsische Gesellschaft. d.

Wissenschaften.

Zoolog. Institut.

Marburg.

Anatom. Institut.

Gesellschaft zur Beförderung d.

gesamten Naturwissenschaft.

Zoolog. Institut.

155

Metz.

Societe d’hist. natur. de la Moselle.

Verein fiir Erdkunde u. Naturwis-

senschaft.

München.

Anatom. Institut.

Gesellschaft f. Morphologie u. Phy-

siologie.

Zoolog. Sammlung.

Münster i. Westfalen.

Westfälischer Provinzialverein f.

Wissenschaft u. Kunst.

Plön.

Biologische Station.

Rostock.

Anatom. Institut.

Zoolog. Institut.

Strassburg.

Anatom. Institut.

Gesellschaft f. Wissenschaft, Land-

wirtschaft u. Kunst.

Zoolog. Institut.

Tübingen.

Zoolog. Institut.

Wiesbaden.

Nassauischer Verein f. Naturkunde.

Würzburg.

Anatom. Institut.

Physikalisch-mediein. Gesellschaft.

Zoolog. Institut.

Great Britain & IRELAND.

Aberdeen.

Natural History Museum.

Bangor.

University College of North Wales.

Belfast.

Queen’s College.

Birmingham.

Birmingham Nat. Hist. & Philo-

soph. Society.

156

Bristol.

University College.

Cambridge.

Balfour Library.

Cardiff.

University College of South Wales

& Monmouthshire.

Cork.

Queen’s College.

Dublin.

Univ. College.

Univ. of Dublin.

Dundee.

Univ. College.

Edinburgh.

Royal Society of Edmburgh.

Zoolog. Museum.

Glasgow.

Laboratory of Nat. Hist.

Leeds.

Yorkshire Naturalists’ Union.

Liverpool.

Biological Dep’t.

Liverpool Biolog. Society.

London.

Howes, Prof. G. B.

Linnean Society.

Nature, Editor of.

Natural Science, Editor of.

Nat. Hist. Museum, South Ken-

sington.

Royal Asiatic Society.

Royal Microscopical Society.

Royal Society.

Royal College of Science.

University College.

Zoological Society.

Manchester.

Manchester Microscopical Society.

Owens College, Zoolog. Dep't. of.

Nottingham.

Nottingham Naturalists’ Society.

Oxford.

Biolog. Dep’t. of the University.

Plymouth.

Marine Biolog. Ass. of the United

Kingdom, Laboratory of the.

St. Andrews.

University.

Tring.

Zoolog. Museum.

Hozzaxp.

Amsterdam.

Kon. Zoologiscli Genootschap “Nat.

Artis Magistra.”

Zoologisch Laboratorium en Muse-

um.

Groningen.

Zoolog. Institut van Rijks-Univ.

Helder.

Zoolog. Station.

Leiden.

Zoolog. en zootom. Laboratorium.

Rotterdam.

Nederlandsche Dierkundige Ver-

eeniging.

Utrecht.

Zoolog. Museum en Laboratorium.

Huncary.

Vide AusrRIA-HunGaRY.

IRELAND.

Vide Great Britain & IRELAND.

Irıry.

Bologna. |

Gabinetto di zoologia di R. Uni-

versità.

Cagliari, Sardegna.

Laboratorio e museo di zoologia e

d’anatom. comparata di R. Uni-

versità.

Firenze.

R. Museo di storia natur.

Genova.

Museo zoologico.

Messina.

Gabinetto di zoolog., anat. comp. e

Fisiologia.

Modena.

Instituto di zoologia ed anat. comp.

Napoli.

Società dei naturalisti.

Statione zoologica.

Padova.

Instituto di zoolog. ed anat. comp.

Palermo.

R. Università.

Pisa.

Gabinetto zoologico-zootomico.

Roma.

Gabinetto di zoolog. di R. Univer-

sitä.

R. Accademia dei Lincei.

Società per gli studi zoologici.

Torino.

R. museo zoologico.

JAPAN.

Tokyo.

Asiatic Society of Japan.

Deutsche Gesellschaft f. natur- und

Volkerkunde Ostasiens.

Java.

Batavia.

Koninklijke Natuurkundige Vere-

eniging in Nederlandsch Indie.

Buitenzorg.

Jardin botanique.

157

Maracca.

Singapore.

Raffles Museum.

Mexico.

Museu nacional.

New ZEALAND.

Christchurch.

Canterbury College, New Zealand

Univ.

Dunedin ( Otago ).

Univ. of Otago.

Norway.

Bergen.

Museum.

Christiana.

Zootomisk Institut.

PortuGat.

Coimbra.

Museo zoologico de Universidade.

Purcrppine [suanps.

Manilla.

Real y Pontificia Universidade de

Santo Tomai.

Roumanra.

Bukarest.

Institul de Morphologie.

Russia.

Charkow.

Zoolog. Museum d. kais. Univ.

Dorpat (Jurjew).

Zoolog. Museum d. kais. Univ.

Helsingfors.

Zoolog. Mus. d. kais. Alexanders-

Univ.

158

Kasan.

Zoolog. Cabinet u. Mus. d. Kais.

Wladimir-Univ.

Moskau.

Societé impér. des naturalistes de

Moscou.

Odessa.

Kais. neurussische Univ.

Tobolsk.

Museum.

Tomsk.

Zoolog. Institut d. kais. Univ.

Warschau.

Zoolog. Cabinet u. Labor. d. kais.

Univ.

SCOTLAND.

Vide Great Britain & IRELAND.

SIBERIA.

Vide Russia.

SPAIN.

Madrid.

Facultad de ciencias.

SWEDEN.

Lund.

Zoologiska Museum.

Stockholm.

Naturhist. Riks-Museum.

Zootomiska Institutionen.

Upsala.

Zoologiska Museum.

SWITZERLAND.

Basel.

Zoolog. Institut.

Bern.

Naturforschende Gesellschaft.

Zoolog. Institut.

Genève.

Laboratoire d’anat. comp. et de

microscopie.

Musée d’hist, natur.

Neuchatel.

Société des sciences natur.

Zurich.

Concilium bibliographicum.

Zoolog.-vergl.-anat. Laboratorium.

UNITED STATES or AMERICA.

Ann Arbor, Mich.

University of Michigan.

Austin, Tewas.

Univ. of Texas.

Baltimore, Md.

Johns Hopkins Univ.

Berkeley, Cal.

University of California.

Boston, Mass.

Public Library of the City.

Champaign, Ill.

State Lab. of Nat. Hist.

Chapel Hill, N. C.

Univ. of North Carolina.

Chicago, Ill

Univ. of Chicago.

Warase, Dr. 8.

Wuirmay, Prof. C. 0.

Hanover, N. H.

Dartmouth College.

Ithaca, N.Y.

Cornell University.

Lincoln, Nebr.

Univ. of Nebraska.

New Haven, Conn.

Yale University.

New York City.

Columbia Univ., Biolog. Dep’t. of.

N. Y. Academy of Sciences.

Science, Editor of.

Palo Alto, Cal.

Leland Stanford Univ.

Philadelphia, Penn.

Academy of Nat. Sciences.

American Philosophical Society.

American Naturalist, c/o Prof.

Frazer.

Princeton, N. J.

Princeton College.

Providence, ‘R. I.

Brown University.

San Francisco, Cal.

California Acad. of Sciences.

Salem, Mass.

Morse, Prof. E. 8.

Washington, D. C.

Biological Society of Washington.

‘Microscopical Publishing Co.

139

National Acad. of Sciences.

National Museum.

Smithsonian Institution.

STEJNEGER, Dr. Leonhard.

U. S. Surgeon-General’s Office,

Williamstown, Mass.

Williams College.°

Worcester, Mass.

Clark University.

West InpIrs.

Kingston, Jamaica.

Institute of Jamaica.

List of Publications received by the Zoological Society of

Tokyo before the issue of the Annotationes.

1. Bolletino della Societa Romana per gli studi Zoologici.

Complete

vol. IIT (1894); vol. IV (1895); vol. V. (1896).

2. Bulletin de la Société de France.

3. Revue des Sciences Naturalles 4 St-Petersbourg.

From the Society.

Complete vol. XX (1895).

From the Society.

Complete vols.

for 1890, 1891, 1892, and 1893.

From the Publisher.

4. Comptes rendus des Sciénces de la Societe Imperiale des Naturalistes

de St-Petersbourg. No. 7 and 8 for 1895, No. 1-5 for 1896,

No. 1 for 1897.

From the Society.

5. Travaux de la Société des Naturalistes de St-Petersbourg, Section

de Zoologie et de Physiologie. Complete vols. for 1894 and 1895.

From the Society.

6. Travaux de la Société des Naturalistes de St-Petersbourg, Section

de Botanique. Vols. for 1894 and 1895.

From the Society.

7. Travaux de la Société des naturalistes de St-Petersbourg. Section

de Geologie et de Mineralogie. Vols. XXIII and XXIV for

1895 and 1896, and No. 2 of vol. XXI.

From the Society.

160

10.

17.

18.

19.

Actes de la Société Scientifique du Chili. i

liv. 5 Tome II; liv. let 2 Tome III; liv. 1-5 Tome V; liv.

152,8, DSL Orne Vie

È From the Society.

Anales de la Sociedad Ceintifica Argentina ;

entrega 1-3 and 6 Tomo XL; entrega 6 Tomo XXXIX;

entrega 1, 2, 4-6 Tomo XLI; entrega 1-3, 5, 6 Tomo XLII;

entrega 1-5 Tomo XLIII.

From the Society.

The Microscope.

No. 3 vol II; No. 1-5, 7, 9, 10-12, vol. III ;.No...1-12, vol.

IV; 1-9, vol. V. |

From the Microspical Publishing Company.

Proceedings of the Academy of Natural Sciences of Philadelphia.

Part II and III for 1895; part I for 1896.

From the Academy.

Verhandlungen der Deutschen Zoologischen Gesellschaft.

Jahrgang 5 and 6 for 1895 and 1896.

From the Society.

Congreso Cientifico General Chileno. De 1894.

» Videnskabelige Meddelelser fra den naturhistoriske Forening

Kjobenhavn for Aarat 1895.

Revista do Museu Paulista, 1895.

Bolletino dei Musei di Zoologia ed anatomia comparata della R.

Universita di Genova. No. 54, 55 of 1896.

Etude sur le développement embryonaire du Gammaras pulex,

reprint.

From the authoress, Mde. Marie Ressyskaia-Kojernikova.

Beitrige zur feineren Structur des Integmentes der Hatteria

punctata.

From the author, G. Osawa.

The Indian Magazine and Review. |

New Series, No. 74, vol XX VIII.

From the Publisher.

PRINTED AT THE ‘ Tokyo Prrtine Co., Lv.” Tokyo, JAPAN.

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CONTENTS.

Note on an Amphioxus obtained in Amakusa, Kyushyu .................H. Nakagawa.......... 125

On a New Species of Elasipoda from Misaki.................................. K. Miura 133

Preliminary Note on the Development of the Pronephros in Pe-

ÉTOMYZONT. ue vacreovennvesecetesseneneee fesse Mere ee rate eee ae des Ei 137

Sur une nouvelle espèce japonaise du genre Lucernaria...............-.- AS Oh irra na 141

Sur une nouvelle espèce japonaise du genre Phoronis.................. sullo OLD nee. de 147

Miscellaneous Notes.........-... clerici ion ieenatz aeree a ento r hen nenn. PORTER Sine eno pese eee 149

The Occurrence of Sphærothuria bitentaculata; Ludwig in the Sagami Seas.—Contri-

butions to the Morphology of Cyclostomata. I. On the Formation of the Heart in

Petromyzon, by S. Harra.—Zoological Society of l'okyo.

Personal News... iii cesser RE RSA ELIA PESI Ce A RE 151

List of Publications received in exchange for the Annotationes

until October, 1897, arranged alphabetically according to Au-

thors or Societies, ..ic.....+-usexdecures sy (e RRCRRRE ERE Renee apri 152

List of Names to which the Annotationes are regularly sent................................, 152

List of Publications received by the Zoological Society of Tokyo

before the issue of the Annotationes....sr.-.1---s--scersisiezionera zones scanio nenepene nente 159

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