ae

ae

fe

List of Fascicles issued to 22nd June, 1929 (contiaueDe —-

Part IV. CoLgopTERA.

Fasc. 1. Carabide. By H. E. Andrewes. 9 Eee Dytiscide. By A.

Zimmermann. 2 tone figures. Ad Urchyme 2. Nl Gamer M.B. 2 text-

figures. Hydrophilid: e. ymont. text hee Clayicornia and

Lamellicornia. By G. we 13 text-figures. 7, 4to. 3s.

Fasc. 2._ Heteromera, Boacthaes ee a Bae ‘By K. G.

Blair, B.Sc. 14 text-figures. Elateride. Boas H. van Zwaluwenberg. 10

text-fgures. Meese (uate z). By E. Fleutiaux. Cerambycide. By

Chr. uel ae pte on ade y R. Kleine. 4 text-figures.

eo) ide. Kart fe liteatcheures Proterhinide. By

i rdan, Ph.D.

CIEL: peice? D.Sc., F-R:S. Pp. Dvd, 1928, 4to. 5s.

Fasc. 3. Throscide. By K. G. Blair, B.Sc. 1 text-figure. somelidz,

By S. Maulik, M.A. 18 text-figures. Pp. 175-215. 1929, 4to. en

Fasc. 4. Platypodidae and Scolytidae. By C. F. C. Beeson, De 13 text-

figures. Pp. 217-248. 1929, 4to. 2s. 6d.

Part V. HYMENOPTERA.

Fasc. 1. Apoidea, Sphecoidea, and Vespoidea. By R. C. L. Perkins, D.Sc.,

. and _L, Evelyn Cheesman, F.ES., ‘S.” 12 text-hgures. Larride.

By Francis X. Williams. 12 text-figures. Formicide. By Dr. F Santschi.

9 text-figures. Pp. 1-58. 1928, 4to. 5s. i

Part VI. Duprera.

Fasc. 1. Streblide and Nycteribiide. By L.Falcoz. 7 text-f wee Biles

boscide. By G. F. Ferris. 6 text-figures. Pp. 1-21. 1927, 2s. 6d

Fasc. 2. Sees By F.W.Edwards,M.A. 20text-figures. Cecilomyine.

By H. F. Barnes, B.A., Phi D. 4 text-figures. Pp. 23-1 1928, 4to. 5s.

Fasc. 3. Stratiomyude, Tabanide and settee By Gone Ricardo. 6 text-

gures. rve of erate nde. :

Del cbopeniae) Sepa ed mb, Sc. ae "8 text-figures. Sarcophagide. By

xton, M.A. text-figures. Muscide. By J. R. Malloch.

Pp. 109-175. 1929, 4to. at

Part VII. Otner Orpers or INsEcts.

Fasc. 1. Isoptera: tomy) Te oe Gerald F. Hill. 14 text-figures and

plate. Odonata. By Lt.-Col. raser, ILM.S., F.E.S. 5 text-figures.

Pp. 1-44. 1927, 4to. 2s. 6d.

Fasc. 2. Plectoptera. By R. J. Tillyard, ae (Cantab.), F.R.S., and J. A.

stage. 2 text-figures. Si honeptera. uxton, M.A. Thysano tera.

By Biche»: Bagnall, FR. LS: Giert Ruares Pp. 45-76. 1928, 4to.

bee Fe Nialone ‘tha By J. Teen D.Sc. 2 text-figures Anoplura. By

Buxton, ‘Trichoptera. y Martin # osely. gure,

ese ees By P. Esben-Petersen. | text-figure an lates. Apterygota.

By George H. Capen Se. 32text-figures. Pp. Ta 1928, 4to. 2s. 6d.

Parr VIII. TrrrestriaL ARTHROPODA OTHER THAN INSECTS.

Fasc. |. Isopoda Terrestria. By Harold G. Jackson, DSc. 2 plates. Scor-

pionoidea. By P. A. Buxton, M.A. Pseudo-scorpiones. By A. Kastner. IT

ex eutes Acarina. By Stanley Hirst. 2 text-figures. Je 1-27. 1927,

0. 2s. éd.

Fasc. 2. _Myriopoden (Myriopoda). By C. Attems. 4 re hauee Araignées

(Araneida). By Dr. Lucien Berland. 79'text-figures. Pp. 29- oe 1929, 4to. 2s. 6d.

uxton, M.A. text-figures. »

Date Issued.

19th December, 1927.

25th February, 1928.

23rd February, 1929.

nd Tune 1909)

25th February, 1928.

2374 Julat 1927.

23rd June, 1928.

11th May, 1929.

28th May, 1927.

23rd June, 1928,

28th July, 1928.

23rd July, 1927.

22nd June, 1929.

eS arom tata stag

Aecpler’s Seedy.

5 f / ae ii

BRITISH MUSEUM (NATURAL History) /!#<4 AE.KM LR

ae

INSECTS OF SAMOA

AND OTHER SAMOAN TERRESTRIAL

ARTHROPODA

PART IX.

FASC. 1. Pp. 1-32

DESCRIPTION OF THE ENVIRONMENT

By P. A. BUXTON, M.R.CS., |

LONDON SCHOOL OF HYGIENE AND TROPICAL MEDICINE

WITH TWO TEXT-FIGURES AND SIX PLATES

LONDON :

PRINTED BY ORDER OF THE TRUSTEES OF THE BRITISH MUSEUM

es SOLD AT

_ THe Berrish Muszum (Natura History), CRomMwELL Roap, S.W.7

AND BY

B. Quaritcy, Lrp.; Duzau & Co., Lrp.; aNp Tax Oxvorp University Prrss.

4 Py LOGO AN i,

Issued 22nd November, 1930.] [Price Two Shillings and Sixpence.

INSECTS OF SAMOA

AND OTHER SAMOAN TERRESTRIAL

ARTHROPODA

Although a monograph, or series of papers, dealing comprehensively with

the land arthropod fauna of any group of islands in the South Pacific may be

expected to yield valuable results, in connection with distribution, modification

due to isolation, and other problems, no such work is at present in existence.

In order in some measure to remedy this deficiency, and in view of benefits

directly accruing to the National Collections, the Trustees of the British

Museum have undertaken the publication of this account of the Insects and other

Terrestrial Arthropoda collected in the Samoan Islands, in 1924-1925, by

- Messrs. P. A. Buxton and G. H. E. Hopkins, during the Expedition of the

London School of Hygiene and Tropical Medicine to the South Pacific.

Advantage has been taken of the opportunity thus afforded, to make the studies

as complete as possible by including in them all Samoan maierial of the groups

concerned in both the British Museum (Natural History) and (by courtesy of

the authorities of that institution) the Bishop Museum, Honolulu.

Tt is not intended that contributors to the text shall be confined to the —

Museum Staff or to any one nation, but, so far as possible, the assistance of the

leading authorities on all groups to be dealt with has been obtained,

The work is divided into nine “Parts” (see p. 3 of wrapper), which are

subdivided into “‘Fascicles.’”’ Each of the latter, which appear as ready in

any order, consists of one or more contributions. On the completion of the

systematic portion of the work it is intended to issue (in Part IX), a general

survey, summarising the whole and drawing from it such conclusions as may

be warranted.

A list of Fascicles already issued will be foued on pp. 3 and 4 of this wrapper.

E. E. AUSTEN,

. Keeper of Entomology.

British Museum (Natura History), ;

CROMWELL Roap, S.W.7.

INSECTS OF SAMOA

Part IX, Fasc. 1

DESCRIPTION OF THE ENVIRONMENT

By P. A. Buxton, M.R.C.S.

THE ISLANDS.

GEOGRAPHY.

BEFORE we proceed to describe the position and structure of Samoa, it would

be well to observe its general relation to other archipelagoes. So far as its

tropical boundaries are concerned, Oceania may be said to lie to the east of

New Guinea (see map, Text-figure 1). It is generally divided into Melanesia

and Polynesia, and this arrangement is convenient for our purpose * though the

basis is ethnographical. The principal archipelagoes in Melanesia are the

Bismarcks, the Solomons, the Santa Cruz Group, the New Hebrides and New

Caledonia. To the east lies the great archipelago of Fiji, which is generally

regarded as a part of Melanesia, though in many respects it is a boundary region

with some Polynesian characteristics. Hast of Fiji lies Polynesia, the principal

island groups being Samoa, Tonga, the Cook Islands, the Society Islands and the

Marquesas ; all of these groups contain high volcanic islands. There are also

the following groups, all of them low atolls : the Ellice, the Phoenix, the Tokelau,

the Paumotu Islands and many others. There are also two important archi-

pelagoes which are ethnographically Polynesian, but so different in fauna as to

be excluded from Polynesia for our purposes; the Hawaiian Islands, lying on

the Tropic of Cancer, far removed from other Oceanic Islands, and possessing

a remarkable fauna; and New Zealand, entirely extra-tropical, and therefore

* No reference is made to the Caroline, Ladrone, Marshall, Gilbert Islands, etc., generally

grouped as “ Micronesia’ ; it seems that the fauna is not closely related to that of Samoa.

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THE ISLANDS. 3

unlike the rest of Polynesia, even if it had not its own very ancient and peculiar

fauna.

Samoa lies well within the tropics at a great distance from any large mass of

land (Text-figure 1); the position of the islands accounts to a great extent for

their climate (page 10) and their fauna (page 19). As the islands are about

14° S., they lie in the southern equatorial current, a surface stream which

crosses the Pacific in these latitudes from east to west. This body of water

is very wide, extending from a few degrees north of the equator down to lat.

20° oreven 25° 8. It flows throughout the year and gives off a number of currents,

which pass away in a southerly direction. The relation of this current to the

distribution of terrestrial life is apparent. The isolation of Samoa, which is a

Polynesian word for the archipelago and not for any one island, is very much

oreater than first appears ; it should be remembered that the ten-degree squares

on the map have sides of approximately 600 miles, so that Samoa is about

130 miles from the north of Tonga, and 500 miles from Fiji. Moreover, the islands

themselves are small compared with the immense ocean; the area of Savaii

is only 730 square miles, and this is more than half of the total area of the archi-

pelago. If one compares Samoa with two better-known Hawauan Islands,

Savaii is almost the same size as Maui, and only a sixth of the size of the island of

Hawaii. What is true of Samoa is true of Pacific Islands in general; one must

never forget the vastness of the ocean, and the great expanses of sea which

separate islands and archipelagoes from one another. According to Daly (1916),

there are 73,000 square miles of land, and 35,000,000 square miles of water

in Oceania, so that the proportion of land to water is as one to five hundred ;

and yet Brigham’s “ Index ” gives the names of 2,600 islands.

GEOLOGY.

In this vast area, geological and especially petrographic surveys have been

few, but one definite conclusion seems to be established, and it bears directly

on these studies on the fauna of Samoa. A line drawn from New Zealand and

the Kermadecs, through Tonga and Fiji, to the New Hebrides and the Solomon

Islands will mark an important geological boundary. In the islands which I

have named, and in islands to the west of this line, some evidence exists of

former continental areas. There is detailed petrographic evidence in support

of this view, and in nearly all the islands mentioned there is great and recent

elevation. Here, then, is the probable edge of a continent, and east of it lies the

4 INSECTS OF SAMOA.

“oreat Pacific basin.” Hast of the line there is no petrographic evidence *

of continentality, and the ocean is continuously deep. All the islands are

either volcanic, as Samoa, or atolls of coral limestone, as Rose island and the

Ellice group. From islands of either type it is very difficult to obtain evidence

of the previous geological history of the area, unless indeed one accepts the

Darwin-Dana hypothesis that atolls are evidence of subsidence. But even if

that hypothesis is in the main true, and modern opinion tends to favour it

(Davis), 1t can hardly stand by itself as sole evidence for the previous existence

of a great land mass.

The geological history of the Pacific has been recently discussed by Gregory.

Few would disagree with his conclusions that the ocean has been*smaller than it

is now: the previous existence of land masses both in the north and the south

is almost a matter of general consent. But our problem is the centre. Gregory

holds that “ lands survived across the Central Pacific apparently until the Lower

Kainozoic.” With the geological evidence I am not competent to deal, but one

must remember that strata and fossils are absent, so that it 1s hardly surprising

that there is a difference of opinion in geological circles. One should also

remember that even an elevation of 10,000 feet, which would unite all Melanesia

to New Guinea, and New Zealand, Fiji, Tonga and Norfolk Island to Queensland,

would leave Samoa surrounded by sea. But even if we admit a land mass in the

centre of the Pacific in Lower Kainozoic times, we must suppose that it sank

completely, for it seems incontestable that the present fauna of Samoa is truly

oceanic, and that neither the islands nor their flora are a remnant of a great

land. I think that this conclusion will be admitted when the insect fauna

is discussed at a later date ; the other elements of the fauna (page 19) support

this view.

I have discussed the geological evidence with some hesitation, realising its

importance as a basis for faunistic work. The most valuable general papers

are those by Marshall, Gregory, and Daly (1916); a full recent discussion of

atolls and coral reefs has been published by Davis ; Thomson has written on the

geology of Western Samoa, and Daly (1924) on American Samoa. The papers

mentioned contain lists of references, and make it unnecessary for further

papers to be quoted here. One would be glad to see fuller geological surveys

* But see Daly, 1924: the question is raised whether the occurrence of quartz-bearing

trachyte in Tutuila, Samoa, should not be taken as evidence of “ continentality.”

THE ISLANDS. 5

made in many parts of Oceania; it is also most desirable that a competent

person should review the evidence, with particular reference to Wegener’s

hypothesis, and to modern views on geodesy.

With regard to Samoa itself, no elevated coral limestone sede the islands

consist of volcanic rocks, principally olivine basalts according to Thomson.

Daly (1924) holds that Tutuila is the oldest of the Samoan islands; it has no

active volcano, and no crater lakes ; the oldest lavas in Tutuila “ are no younger

than an early stage of the Pleistocene period, and may be Pliocene, if not older.”

The Manua islands, to judge from their degree of dissection, are more recent

than Tutuila. Savaii, with active volcanos, is thought to be the most recent

island in Samoa ; Upolu, with crater lakes but no active volcanos, is intermediate

in age between Savaii and Tutuila.

TOPOGRAPHY.

I now propose to give a description of the structure of Upotu, the island

most familiar to me and most fully explored and described by other travellers.

The reader must understand that though Upolu is only about twice the size of

the Isle of Man, much of the interior is unmapped, and indeed absolutely unknown

to white men (and almost equally unknown to the present generation of Samoans).

The island is elongate, some 45 miles long and 8 to 12 miles wide; the area is

430 square miles. In the part of the island south of Apia there is a clearly

distinguishable main ridge, nearly flat and a couple of miles wide. Its altitude

is 2,000 to 2,200 feet. Malololelei is a farmstead in a clearing, a little below the

ridge on the north side; it is used as a rest-house, and is an admirable centre

for collecting. From it the island falls steeply to within a few hundred feet of

sea-level on the north and south sides. Below this level the slope is much less

steep, and the ground is cultivable. Along the ridge there is a chain of many

old craters running from a little north of west to a little south of east. Some of

these craters are filled with water, and are typical “crater lakes.’”’ Lanutoo

is the only one which is easily reached : it lies on the rather flat ridge of the island,

above which the rim of the crater rises steeply perhaps 100 feet. The water-

level is perhaps 100 feet below the crater rim, and the lake circular and a quarter

of a mile in diameter. Hast of Lanutoo there is a considerable area of “ red

clay ” (no doubt a rotted tuff) on the main ridge of the island. I do not know

of any other area of this material on Upolu. Many of the craters are dry and

incomplete, as most of the perimeter has disappeared, leaving a steep crescentic

OF SAMOA.

INSECTS

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THE ISLANDS. 7

ridge, narrow on the top; Tanua, Vaitoa and Le Pue are examples of this type.

Few of these craters rise much beyond 2,000 feet ; one, which I have not visited,

reaches 3,600 feet, the highest point in Upolu. The higher parts of Upolu are

almost unknown except in the neighbourhood of Malololelei ; it is probable that

a rich endemic fauna remains undiscovered.

In the hills the rainfall (page 16) is very heavy ; on the north side of the ridge

of Upolu it is about 200 inches, and one presumes that on the south side it is

higher still, owing to the 8.E. Trade Wind. Much of this water is carried off

by a series of gorges which lie roughly parallel to one another, and run north-

wards and southwards. The water descends by a series of waterfalls and rapids,

till it reaches the lower and less steep parts of the island (Plates 1, 2, and 3).

The gorges in which these streams run are deeply cut, and the sides are very steep

and in many places unclimbable. These gorges are very numerous, so that the

intervening ridges are narrow ; some of them are mere knife-edges. It 1s there-

fore almost impossible to traverse the island from east to west, except round the

coast or along the main ridge. If one set out to go from east to west crossing

the gorges and the intervening ridges, | very much doubt if one could travel

four miles in a day.

If one starts on the ridge of the island and follows any small stream downhill,

one finds that the banks are a few feet high; but where it leaves the broad

ridge and commences its steep descent, it passes very suddenly into one of these

gorges with high precipitous sides. I believe that many of them are old lava

tunnels, of which the roof has collapsed, and that this explains the abrupt transi-

tion from banks a few feet high to precipitous walls. This is clearly true of one

stream about half a mile west of Malololelei. This stream drops suddenly, like

so many others, into a steep-sided gulley, in which it runs for several hundred

yards ; it then enters a lava tunnel without altering the direction of its course.

The tunnel is circular, about 20 feet in diameter, and flat bottomed (Plate 4, B).

It is fairly straight, and has one short branch. It runs steeply downhill for

perhaps 200 yards, with the stream on its floor, or beneath its floor. At this

point the roof has caved in for 30 yards: apparently this happened quite

recently, for the edges of the cavity are steep. After this short break the

tunnel continues downhill, but one can only follow it 30 or 40 yards as it is

filled with blocks of stone. It is clear that this stream flows in a lava-tunnel,

which is in course of becoming a steep-sided open gorge. Numerous other lava

tunnels are known in various parts of Samoa (Thomson).

8 INSECTS OF SAMOA.

As these mountain torrents reach the lower, less: steep parts of the island,

they unite with one another, but the total volume of water becomes visibly

less and less: it appears that the greater part of the drainage from the hills is

carried away by subterranean channels. This water again reaches the surface

near high-tide mark in a series of springs, which are found on most parts of the

coast. There is hardly a village without its spring and bathing pool.

The lower slopes of the hills are much less steep than the upper, and they

pass gradually, in many parts of Upolu, into a zone of nearly flat ground close

to the coast. Some of these areas are small delta plains in the mouths of rivers.

Between Apia and Mulifanua this zone of cultivable ground is so wide and so

nearly flat that one might take it for an ash plain, or even for the floor of an old

coral reef lagoon. Itis neither. It is a plain of lava which has rotted into black

soil full of boulders of lava in some places, but in others the lava persists as ribs

running down from the central part of the island. Close to the sea it is rather

flat and uniform, owing to inblown coral sand ; farther back it 1s much rougher.

It cannot be ploughed anywhere by reason of ridges of lava and basaltic boulders.

There is no evidence of elevation in the shape of elevated coral or old shore

benches.

It is on this relatively flat ground close to the sea that practically every

village is placed. Here also one finds the cultivation, the introduced plants and

weeds and many of the introduced insects. (Plate 4, C.)

The actual beach, wherever one occurs, is white, and consists of fragments

of coral and shells pounded up so that it appears tobe sand. (Plate 4, A.) The

beach runs down to a lagoon full of coral, with occasional patches of the same

“sand” in which the plant Halophila grows; it is there that the submarine

midge Pontomyia (vi, 64)* may be taken at appropriate seasons. The lagoon

is separated from the ocean by the fringing reef, which shelters most of the shore

of Upolu. In places, however, there is no lagoon, for the black cliffs of basalt

form an “iron-bound” coast, and fall straight into deep water without any

fringing reef. These basalt cliffs are the ends of ancient lava-flows, which

came from the interior of the island, filled the lagoon, covered the reef and

plunged into deep water. They are even more characteristic of Sava than

of Upolu.

* References to other “ Parts” of the present work are quoted in this form, the words

* Part” and “ page ”’ being omitted,

THE ISLANDS. 9

The other Samoan islands may be dealt with more shortly. Sava, the

largest island in the group, is about 47 miles long, with a greatest width of

27 miles. It contains by far the highest mountains in Samoa, the summit being

about 6,000 feet above sea-level. The higher parts of Savaii are almost unknown,

the summit having been reached only twice so far asis known. Mr. EH. H. Bryan

of the Bishop Museum, Honolulu, collected for several days up to 5,000 feet ;

no other insect collector has worked in the higher mountains of Savaii. Savail

contains an active crater, and there are very large areas of rough lava erupted at

various periods, including several which are of known age ; even the flow of about

the year 1760 is only covered with a poor type of low forest, consisting of very

few species of trees, and among the trees the surface of the lava is still exposed,

bare of humus.

Thomson has already described Apouima, of which the area is about 2 square

miles. It is a tuff crater, open on the north, the bottom of the crater a little

above sea-level. The outer slope is very steep, in many places a precipice, bare

of vegetable life. The inner slope is less steep and covered with forest.

I have been on Apolima, and also on Nuvu TELE, the structure of which has

not been described so far as I know. Like Apolima, it is a breached tuff crater.

It is larger than Apolima, but very similar to it. The bottom of the crater is

flat, and has been cultivated, and there is at least one perennial stream. From

the bottom the sides rise very steeply, but they can be climbed in many

places. The crescentic top of the island is very narrow, in many places less

than 10 feet wide. I estimated it to be 400 feet above sea-level. The outer

side of the island is precipitous. There is a coral reef across the mouth

of the little harbour, where the tuff cone is breached. Round the outside

of the island there is no fringing reef, and the reefs shown between this island

and Nuulua, on Admiralty Charts and other maps, are non-existent. I have

looked down on continuous deep blue water in this direction from the top of

Nuu Tele. .

There are a number of smaller islands lying close to Upolu. The largest,

and the only one inhabited by man, is Manono, which lies off the N.W. coast

of Upolu ; it is within the fringing reef which encircles that part of Upolu, and

can hardly be expected to be of interest faunistically.

The islands so far described form “‘ Western Samoa,” and are a Mandatory

Territory administered by New Zealand. The remaining islands form “ American

Samoa.” The distinction is not only political, for the sea between Upolu and

2

10 INSECTS OF SAMOA.

Tutuila is nearly 6,000 feet deep. One is, therefore, prepared for considerable

differences between the faunas of the two parts of the archipelago.

TuruILa has an area of only 54 square miles, but it has a disproportionately

long and irregular coastline. The geology has been discussed fully by Daly

(1924) ; the U.S. naval chart of this island is much more complete and accurate

than any existing map of Savaii or Upolu.

I have never visited the Manua Grovp, and know no general account of the

islands; the total area of the group, which includes several islands, is only

18 square miles.

Rose Istanp, or Rose Atoll, which is included in Samoa on general geo-

eraphical grounds, is an uninhabited atoll, 140 miles east of the Manua group.

It has been well described by Mayor. To the biologist, it has no connection with

the other Samoan islands, for even among atolls it is unusually barren.

THE CLIMATE.

Many years ago the German Government opened a meteorological Observa-

tory on a peninsula close to Apia. Its work was not interrupted by the war, and

its records furnish valuable information about nearly all the climatic factors which

are studied by meteorologists. It is the most important centre of meteoro-

logical work in the tropical Pacific.

The naturalist may well regard Upolu as a type of tropical island, lying far

from disturbing continents. He would like to build on the good foundation

laid by the meteorologists, and make a profound study of the climate, considered

as a part of the environment in which the plants and animals live. This work

would require many years, for when the meteorologist has studied the tempera-

ture in a ventilated white screen, the biologist wants to know what differences

exist between the forest and the shore, or the rat’s hole and the bird’s nest:

in the white screen he finds no living thing, unless it be an earwig. Again, the

meteorologist’s mean rainfall is a sound, if conventional, foundation, but the

botanist knows that the trees on the two sides of a hill receive different amounts

of rain, and at different seasons, and that the canopies of the trees distribute

the rain differentially among the undergrowth. In the past we biologists have

relied too much upon the meteorologist ; we have forgotten that he is studying

the dynamics of the atmosphere, and if his facts do not meet our needs, then we

must collect our own. ‘To him the most important instrument is the barometer,

THE CLIMATE. dal

which is no more use to us than an astrolabe ; and it is because we have followed

his lead too closely that we still lack any adequate conception of the climate of

a tropical island as it affects the fauna and flora. I shall therefore use the

meteorological foundation and build up as far as I can a general picture of the

climate of Samoa as the biologist sees it. I shall feel at liberty to generalize,

inasmuch as tables, facts, and graphs have been published elsewhere.*

SoLAR RADIATION.

Let us first study Solar Radiation, though it is difficult and our knowledge

is incomplete: we put it first because the many types of radiation which we receive

from the sun, and the differences in their seasonal distribution, are the most

important part of the climate so far as the plants and animals are concerned.

These seasonal differences depend on changes in the relative position of the sun

andSamoa. The archipelago lies within the tropical zone, between 13° and 14° 8.,

and because of this situation, the sun is vertically overhead at noon twice in the

year, in October and again in February. Between these dates, in the “summer”

of the southern hemisphere, the sun reaches its most southerly position on

21st December, and on that date its zenith angle at Apia is 9° 40’. After passing

the vertical in February, the sun goes northwards, and on 21st June it reaches

its maximum northerly declination, with a zenith angle of 37°12’. In speaking

thus, I have used the convention of a fixed earth and a moving sun. Insolation

should therefore be more intense, because the sun is more nearly vertical, from

about October to about March, and less so during the other half of the year.

Moreover, this seasonal difference would be exaggerated by difference in the

length of the day, for the 21st of December is very nearly 13 hours long, and the

shortest day (20th June) is about 114 hours. Furthermore the earth is nearer

the sun during the southern summer than during the other part of the year.

For these three reasons, more radiant heat would be received by Samoa between

October and March, provided the sky were clear, than at other times of year.

But as a matter of fact the period from October to March is more cloudy than the

rest of the year; during these months the number of clear days per month is

generally below 20, and sometimes below 10. In the other months, or at any

rate from June to September, there are 20-25 clear days (a “ clear’ day is one

with at least seven hours of recorded sunshine). Apart from the presence of

* Buxton and Hopkins, 1927, pages 14 to 50, See also Angenheister,

12 INSECTS OF SAMOA.

actual cloud, the increased. amount of water vapour makes the atmosphere less

penetrable to radiant heat from October to March.

One finds, then, that considerable seasonal differences are to be expected in

the radiation received on Samoa, and that the situation is complicated by a

number of factors. If one endeavours to make actual measurements of radiation

received, one must select a particular part of the solar spectrum for study ; it

is probably easiest to consider first the radiant heat, and its seasonal distribution.

During our stay in Samoa, we took a series of readings with black-bulbed

maximum thermometers, both naked and i vacuo. It is clearly understood

that the readings obtained with these instruments are not capable of exact

physical interpretation; but they have a certain value for purposes of com-

parison. Moreover, we are biologists, not physicists, and we are studying

plants and animals which are exposed to a variety of conditions; they are

heated by the sun’s rays, and cooled by convection currents, and we can under-

stand a little of their state by reading a naked black-bulbed thermometer at

different seasons of the year. The facts we collected revealed a season of less

intense heat radiation in the months from about May to July, and a season of

oreatest mean intensity about December.

There is one objection to the use of maximum thermometers with black

bulbs, whether these are exposed, or in vacuo, for the day’s reading is recorded

at that instant when insolation is most intense, other factors being equal; but

the plant, or the soil, or the insect receives radiation throughout the day, and it

is the sum total which one would wish to study. In fact one wants the mean

temperature of some object exposed to wind, radiation, etc., and so large that

its temperature does not vary rapidly. The island itself appeared to be an

appropriate object, and the soil temperature was taken daily at two depths,

beneath the surface of bare earth. But the results were disappointing, because

the soil is so porous that the rain sinks rapidly through it, and disturbs the

temperature, at any rate as low as 16 inches below the surface.

For one reason or another none of these methods of studying radiant heat

are adequate, especially when one remembers its great biological significance.

The only appropriate instruments seemed to be the pyrheliometers, all of which

are expensive and somewhat difficult to use. They are suited to the physicist

and the observatory, but one does not feel that they meet the needs of

biology, for we wish to study the radiant heat received at a large number

of different stations, and if we cannot have large numbers of absolute

THE CLIMATE. 13

instruments, we must be content with comparative readings, taken at different

seasons, altitudes, aspects and places. For this purpose I devised and used

an instrument, which has been discussed and described elsewhere (Buxton, 1926).

Briefly, it consisted of a blackened bulb, in vacuo, filled with absolute alcohol.

This part of the instrument was exposed to the sun, the heat of which volatilized

some of the alcohol. The alcohol vapour passed by diffusion into a buretite, at

shade temperature, in which it condensed and was measured once a day. With

this instrument we demonstrated :—

1. That the total amount of radiant heat received varied with the seasons,

in accordance with expectation ; in the spring and autumn, when the sun was

most nearly vertical, the monthly totals were between 9 and 12 per cent. of the

annual total; in midwinter (May, June and July) the monthly totals were

between 4:4 and 6°6 per cent. of the annual total.

2. That at the season when the sun was more nearly vertical, an hour of

sunshine produced about twice as much distillate as it did at the season when

the sun was farthest from the vertical.

It is probable that my instrument, or some improvement on it, has considerable

value to biologists, provided that it is remembered that it is not a physical

standard, and that it cannot be used in places in which there are great seasonal

differences in shade temperature. So far as Apia is concerned, our work has

been extended by Thomson’s measurements, taken with the Gorezynski pyrhelio-

meter. In publishing his results he has not been concerned with the reception

of radiant heat by the island of Upolu, but with the transmission of radiation

through different thicknesses of damp tropical atmosphere. Much of his paper

is therefore physical and outside our scope. But he publishes a table showing

the amount of radiation received during bright weather, at different seasons,

and under various conditions prevailing before and after noon. This represents

a material increase in our knowledge of the seasonal and hourly distribution of

radiation at sea-level in the damp tropics.

DuRATION OF SUNLIGHT.

Radiant heat is only one of the many types of solar radiation which are

of importance to plants and animals. A number of facts are known relating

to the duration of daylight, and of bright sunlight, as recorded by a Campbell

Stokes instrument at Apia. The longest day (21st December) is 12 hours

57 minutes ; the shortest (20th June) is 11 hours 19 minutes, but the prevalence

14 INSECTS OF SAMOA.

of rain and cloud in the “summer” makes the distribution of bright sunshine

quite different. In fact August, though the days are relatively short, has the

highest mean record for sunshine (200 hours), and the lowest mean (133 hours)

occurs in February, in spite of the fact that the days are then relatively long.

Putting the same facts in another way, about 40 per cent. of the daylight is

recorded as sunshine in December, January and February; from May to October

the figure is about 50 per cent. or higher, and it reaches 60 per cent. for the month

of August. Bearing this in mind, and remembering also that an hour of sun-

shine in the southern summer will distil twice as much alcohol in my instrument

as an hour in winter, one begins to appreciate how complex the whole subject is.

And beyond this we must remember that there exist whole realms which are

important, but unexplored ; for instance, the seasonal distribution of particular

parts of the visible spectrum (for not all sunlight is equally valuable to the green

plant), and of that part of the ultra-violet which reaches the surface of the earth ;

and the spatial distribution of solar radiation on the north and south sides of the

island, on hill and valley, on leaf and soil.

TEMPERATURE.

Leaving the important but obscure subject of radiation, what knowledge

have we about the more commonplace elements of the Samoan climate ?

The annual mean temperature of Apia is 25-78° C. (78-40° Ff.) ; the mean

of the coldest month, July, is 25-01° C. (77-02° F.), that of the hottest 26-28° C.

(79:30° F.). The difference between the mean temperatures of the hottest and

coldest months (“mean annual range’’) is therefore only 1-27° C. (2:28° F.).

The mean daily range (the difference between the mean monthly maximum and

minimum) is only about 6-4° C. (11-52° F.). The extreme range of temperature

recorded over a space of thirty years is only from 16-4° C. (61-52° F.) to 34-6° C.

(94-28° F.). One may sum it up by saying that there is very little difference in

temperature between day and night and between season and season : this is true

whether one considers means, or maxima and minima. Indeed, one can hardly

think that the seasonal differences in temperature are of any biological significance.

The temperatures which are quoted above were recorded at the Observatory,

which is at sea-level, but at the tip of a peninsula ; its climate is therefore even

more oceanic than that of the rest of Upolu. We made a comparison between

the temperature at the Observatory and that at the Hospital, which is 145 feet

above sea-level and about two miles from the Observatory, though only about one

THE CLIMATE. 15

mile from the sea. Readings taken over a period of nineteen months showed that

the Hospital had consistently higher maxima and lower minima. The difference

between mean maximum (or minimum) at Hospital and Observatory was only

about 2° C.; this appears trivial, but probably has an appreciable effect upon

human beings, who are living close to the limits of the tolerable. The Hospital

is therefore a little more “continental” (if we may apply that term to the

Samoan microcosm) than the peninsula on which the Observatory stands. The

centre of the island has doubtless a still greater daily range of temperature ;

Angenheister states that at Afiamalu, at the centre of the main ridge of Upolu,

at an altitude of nearly 2,000 feet, the mean daily range for the year is 9-6° C.

(17:3° F.); that is to say, that it is half as much again as it 1s at the Observatory.

Apart from differences in temperature between the parts of the island, one wants

to know what is the effect of the forest canopy, or of a roof, upon the area beneath

it. At the Hospital our thermograph was exposed in a standard screen, which

stood in the open, thirty yards from any large building. A hundred yards

away was a residence, well built, and appropriate to the tropics, with wide

verandahs on all sides and a double roof. In this house we selected a draughty

place between two doors which were always open, and exposed a second ther-

mograph. This instrument showed that the construction of the house was

adequate to keep the temperature down during the day, for the maximum in

the house and the screen were nearly the same ; but at night the roof of the house

prevented cooling, in spite of the free ventilation, and the mimimum in the house

was nearly 2° C. above that outside. The effect of a canopy of forest is similar.

We made a direct comparison between the garden at Malololelei, which was open

to the sky and freely exposed to wind, and a position in the edge of the forest,

only about a hundred yards away. In a period of seventeen days the mean daily

range in the garden was 8-0° C., in the forest 40° C. Had we set up instruments

farther into the forest it is probable that we should have recorded still more

equable conditions. Furthermore, the figures quoted above were taken from

thermometers in a ventilated box, fixed in a tree, but insects and other creatures

live in masses of epiphytes, or among dead leaves, or in other situations in which

the mean daily range is probably even less than 4° C. It is right to add that there

are a few situations in which the mean daily range of temperature is greater

than it is in a standard screen. The monthly mean grass minimum temperature

at the Hospital was nearly two degrees Centigrade below the screen minimum,

during the nineteen months in which records were kept. Considering that this

16 INSECTS OF SAMOA.

figure was obtained on bare soil beneath open sky, it is remarkable that the

difference was not greater. But in any case areas of grass or other low vegeta-

tion are few in Samoa, and the grass minimum does not represent an environment

frequented by many animals.

It would be fair to summarize our knowledge of temperature in Samoa by

saying that it is extremely equable and that the differences between day and

night, month and month, or one place and another, are very slight.

RAINFALL.

The mean annual rainfall of Apia is 2,738 mm. (107-8 inches) ; in a period

of sixteen years, the highest and lowest annual totals have been 4,387 mm.

(172-7 inches), and 1,747 mm. (68-8 inches). There is a very regular distribution

of rain through the months, with a single wet season, from November to

February, during which 51 per cent. of the total rain falls. The period from May

to August is much drier, and receives only 16 per cent. of the annual total.

The wettest month is January, with a mean fall of 419 mm. (16-5 inches) ; the

driest month is July, with a mean fall of 71 mm. (2-8 inches). But though the

seasons are so clearly defined and though the driest month receives only a sixth

of the rainfall of the wettest month, it would be misleading to speak of a dry

season. How could one say that July is dry in Apia, when nearly three inches

of rain falls, which is more than the mean rainfall of London for any month of

the year? If the separate monthly totals for sixteen years are considered,

one notices that in that period the monthly rainfall was less than an inch on

only eight occasions ; 1t was above two inches on more than nine-tenths of all

the months. The highest record for any one month in the sixteen years was just

over one metre. Taking the figures for “rainy days’ * for the same period,

the lowest number in one month was three ; and in 80 per cent. of the months

there were more than ten rainy days. It is evident that this very heavy pre-

cipitation must have great biological importance; it drowns some creatures,

prevents the flight of others, and carries large quantities of soil and debris into

the sea. It is also well known that heavy falls of rain are common in Samoa ;

for instance, during nineteen months at the Apia Hospital our highest daily

record was 190°9 mm. (7:52 inches), on Ist May; records of several inches a

day are almost commonplace. It would be of great interest to the biologist

*« A rainy day is one on which more than 0°25 mm. (0°01 inch) of rain is measured.

THE CLIMATE. 17

if the facts accumulated at the Observatory could be tabulated so as to show

the mean number of days for each month in which the rainfall exceeded one inch,

two inches, etc.

With regard to the local distribution of the rain in different parts of Samoa,

little of any value is known. The mean rainfall at the Observatory is 2,738 mm.

(107-8 inches), but this is taken at sea-level and on the lee side of Upolu, and

should be regarded as the figure for the driest part of the island; even at the

Hospital, which is only a couple of miles away, and 145 feet above the sea, the

fall is about 16 per cent. higher. According to Angenheister, the annual pre-

cipitation is probably about 5,000 mm. (say 200 inches) at an altitude of 600-700

metres in the hills in Upolu ; this is approximately true at Malololelei, the centre

round which so much collecting has been done; in the higher mountains in

Savail it is perhaps 7,000 mm. (say 280 inches). At Pago Pago, Tutuila, the mean

annual precipitation for the years 1900 to 1920 was 4,981 mm. (196-1 inches).

The highest and lowest annual totals were 7,224 mm. (284-4 inches) and 3,305 mm.

(129-9 inches). The rainfall of Pago Pago is very high considering its situation

at sea-level, but is probably due to the precipitous hills which surround the

harbour on all sides. The distribution of the rain through the year is much

as itisin Apia ; the driest month, August, has a mean fall of 201 mm. (7-9 inches),

the wettest, February, 615 mm. (24-2 inches). It is evident that the annual

and monthly rainfall of many other stations in Samoa should be studied and

recorded, but though so much more remains to be done, we can be positive that

the local differences in rainfall are very slight, compared with differences in

New Caledonia, or the islands of Hawaiia.

To express the matter in brief, rain is abundant at all seasons, and in every

part of Samoa; there is a clear seasonal difference in distribution, but no dry

season ; by any ordinary standard, deficiency of rain is unknown, and excess

is only too common.

HumMIpIty.

As the temperature is nearly constant, as rain is abundant and well

distributed, and as the islands are surrounded by the ocean, it follows that the

atmosphere is moist at all times and seasons. The means of each of the twelve

months lie between 80 and 86 per cent., but these figures are based only on

readings taken at 7, 14 and 21 hours; had night readings been included the

mean values would have been even higher. It is probable that the slight seasonal

1D all 2

18 INSECTS OF SAMOA.

changes in humidity have no biological significance. Monthly means for relative

humidity will be found elsewhere (Buxton and Hopkins, page 40).

WIND.

Knough has been said to show that the climate of Samoa is warm and damp,

at all times and seasons. The perspiring entomologist soon learns to recognise

that his comfort depends entirely on the wind, for the warm damp air does not

cool him unless it is in motion. From data derived from a recording anemo-

graph at the Observatory, it appears that there is a seasonal difference in the

velocity of the wind, which is consistently higher from May to October, and lower

in the other months. This period, in which the mean velocity of the winds is

greater, is also the season of the regular Trade Winds from the south-east ; for

though the direction of the prevailing winds at all times of the year has an

easterly component, this is increased at that season. ‘The winds and the surface

currents of the ocean therefore approach Samoa from the same direction

(page 3). There is a curious apparent anomaly here; though the fauna comes

from the west, the prevalent wind and current are from the east or south-east.

In spite of this, one cannot assume that the wind has had nothing to do with the

arrival of the insects in Samoa, for the Trades and other easterly winds are a

shallow stream, and at a level of roughly two or three miles above the sea there

is a steady anti-Trade wind, blowing from the west or north at all seasons.

These currents in the upper air are more rapid, and they have also a greater

vertical depth than those which blow at the surface of the earth, and it is possible

that they have been important carriers of insects, etc., from Asia into Oceania.

It is known that these anti-Trade currents have a low humidity, but whethez

this has any biological importance is not certain.

The increased comfort which one feels during the season of the Trade Winds

can best be measured by the katathermometer. I shall not quote the figures

obtained with this instrument (which are given in the work by myself and

Hopkins, page 45), for it measures the loss of heat from a body maintained near

the temperature of a warm-blooded animal, so that its readings cannot relate to

the life of cold-blooded insects. But there can be no doubt that seasonal

changes in the velocity of the wind, in an atmosphere which is almost constantly

hot and damp, must produce seasons of more or less evaporation. These changes

may well be of considerable biological import, for they affect the leaves and

animals, and also the soil itself, but they have not yet been studied.

THE FAUNA AND FLORA. 19

One cannot leave the subject of wind without referring to hurricanes.

According to Visher and Hodge, who have recently summarized what is known

from Australia, and the tropical Pacific, hurricanes are recorded from Samoa

about two or three times a year; but it-is to be understood that few of these

are very violent or destructive. Hurricanes are commoner in Fiji and the

New Hebrides, and the seas to the west, than they arein Samoa. East of Samoa

they are rarer still, so that our archipelago may be said to be on the edge of

the area which is disturbed by these events. In Samoa, and the islands near

it, hurricanes have a sharply defined season ; one-third occur in January, and

three-quarters in the first three months of the year. From May to November

they are extremely rare. They come to Samoa from the north or the east ;

from what is known about tracks of hurricanes generally, one may assume that

they are curving down from the Equator, so that it is not probable that they will

bring many living plants or animals to the Samoan Islands. The thickly

forested hills afford shelter from wind, and one cannot suppose that hurricanes

do serious damage to the insects of Samoa, where they appear to have very little

biological importance.

THE FAUNA AND FLORA.

FAUNA.

Before we proceed to study the insects and to draw such conclusions as may

be possible from the systematic parts of this work, it would be well to review

present knowledge of certain other components of the fauna of Samoa, and of

other archipelagos. In writing this summary I have received much help from

the staff of the British Museum.

The only Samoan Mammats apart from Cetacea are a small rat (Rattus

exulans) and three sorts of bat (two species of fruit bat, Pieropus, and a small

insectivorous bat, Hmballonura semicaudata). The small rat has evidently been

carried about in canoes during the voyages of the Melanesians and Polynesians ;

it is found under different names in nearly all parts of Oceania, southwards to

New Zealand, eastwards to Tahiti, and northwards to the Hawaiian Islands

(Thomas). Its relatives, Rattus concolor, etc., are widely distributed in the

Malay Peninsula and Malay Islands (Miller). With the exception of this rat,

and of various bats, no native mammals exist in any part of Polynesia, or any-

where in Melanesia except the more westerly Solomon Islands and the Bismarck

20 INSECTS OF SAMOA.

Archipelago. The dugong (Halicore), found in the shallower seas which surround

the Malay Islands, New Guinea and Melanesia, does not extend its range so

far east as Samoa. Feral pigs, escaped from villages, have existed since before

the days of Huropean penetration ; there are wild cattle, which owe their intro-

duction to Kuropeans, in the forests of Upolu.

The Brrps deserve rather full discussion, because they are the only extensive

group of animals of which the distribution in the Malay Islands and Oceania

has been satisfactorily studied, so that they have already contributed largely

to our general knowledge of the zoogeography of these regions.

The number of land birds known to inhabit Samoa is only about 34; the

figure is not absolutely certain as some old records are obscure owing to questions

of synonymy, but one may say with some confidence that no unknown species

remain to be discovered. It is clear that they are very much better represented

in the Samoan fauna than are the mammals. About fourteen of these species

are peculiar to Samoa, and others are only known as occurring in Fiji or Tonga,

and Samoa. But though the proportion of endemic species is so high, there

are few which are confined to one or two of the islands of Samoa. The birds

which seem to be endemic to a part only of Samoa are the following: a species

of White Hye (Zosterops samoensis) is only known from Savail, which is the eastern

limit of the distribution of this genus in Oceania ; it is curious, but apparently

true, that the genus has extended east from Melanesia through Fiji to Sava,

and been defeated by the sea separating Savaii from Upolu, a matter of about

nine miles with two intermediate islands. Lalage sharper and Prnarolestes

powelli are perhaps confined to certain islands in the archipelago, but our know-

ledge of them is very limited. The most interesting group in respect of island

endemicity is the kinefishers ; Todirhamphus recurvirostris is endemic to Upolu,

and perhaps Savaii, and apparently absent from Tutuila; outside Western

Samoa the genus is only known from some of the Society Group, and from one

island in the Paumotus. The kingfisher of Tutuila is a species of Halcyon, a

genus of wide distribution absent from Upolu and Savaii; the species in Tutuila

is probably endemic. Even in the genus Péilinopus (Fruit Doves) there is no

species or subspecies peculiar to one island in Samoa; this is remarkable, for

Ptilinopus has been prodigal of endemic species in many archipelagos, and also

in some single islands. The Tooth-billed Pigeon (Didunculus strigirostris) is the

most remarkable bird in Samoa. The genus is endemic and monotypic, and

a family has been created for its reception, though it is doubtful if its peculiarities

THE FAUNA AND FLORA. 21

warrant this treatment. At one period it excited great interest owing to the

facts that it occurred in a remote island, and bore a superficial resemblance

to the Dodo, but it is now held that its anatomical peculiarities are not really

very great. But if the family Didunculidae is allowed to stand, it is apparently

the only endemic family in the land fauna of Samoa, which is characterized by

possessing a great number of endemic species and even genera, but practically

no endemic groups of higher status.

There are certain birds which are distributed eastwards as far as Fiji, but

absent from Samoa and all islands to the east; notable among these are all

hawks (of which Astur and Circus occur in Fiji), and the Woodswallow (Artamus).

The absence of these from the islands beyond Fiji is in accordance with the

general rule that as one passes eastwards some form of animal life is left behind,

whenever the sea between two groups of islands is crossed. But among the birds

there are at least two anomalous species which are absent from Samoa, but

present in islands to the eastwards : Hirundo tahitica is known to be found in the

Bismarcks, Solomons, New Hebrides and Fiji, and also in the Society Islands ;

the genus Conopoderas (Tatare) contains Warblers related to the Reed Warblers.

It is absent from Samoa and the whole of Western Polynesia, but in the Mar-

quesas, Austral and Society Islands a number of endemic forms occur (Murphy

and Matthews).

The sea birds known to occur in Samoa are probably of little interest to us,

though the absence of Cormorants is remarkable.

It will be noticed that the Samoan avifauna is peculiar both in respect

of absentees, and of groups represented in it. It is not possible to explain the

anomalies, as one is tempted to do in an island so far from continents, by saying

that only birds of strong flight can have reached it. This is far from being true,

for Samoa possesses fruit doves, a white eye, and other forest birds which are

never seen to fly far, and it lacks hawks, crows and swallows.

The Samoan birds are derived from the west, and they have little relation

to the specialized avifaunas of the Hawaiian Islands, or of New Zealand, and

none at all to that of America. Admitting their derivation from the west, are

they to be regarded as Australian or Oriental? The question is, perhaps, rather

one of definition than of fact ; it is well to remember that prevalent views on

the distribution of living things are traceable, to a great extent, to Wallace’s

“ Geographical Distribution of Animals.” The regions and sub-regions there

defined, in so far as they relate to our problem, were partly delimited by Wallace

22 INSECTS OF SAMOA.

during his travels in the Malay Archipelago. He had himself passed from Bali

to Lombok, leaving behind him the Finches, Woodpeckers, and many other

Asiatic birds, and meeting for the first time the Honeysuckers (Meliphagidae)

and other families characteristic of the region which he called Australian. His

own vivid recollection of his travels, and the fact that he had to draw most of

his conclusions from the study of birds alone, perhaps led Wallace to be unduly

emphatic in separating the Australian and Oriental faunas in the tropical

islands, which stretch from Malaya to the centre of the Pacific. “‘ Wallace’s

line” certainly marks the eastern limit of many important groups of animals,

and also delimits the westward spread of others. But it is only one of many

lines which the naturalist crosses as he goes eastwards from the Malay Peninsula,

at each of which some familiar and conspicuous group of animals is left behind.

If one pays undue attention to any of these eastward limits, one misses what 1s

essential ; for the fauna of Papua is to a considerable extent Asiatic, though

many Asiatic forms are absent ; the fauna of Melanesia is again largely Asiatic,

as is that of Fiji, and of Polynesia, each successive fauna being less complete

and more oceanic than that which exists to the west of it.

Coming now to Samoa itself, many of the birds are characteristically

“ Australian’ in Wallace’s sense of the word. Even in this limited fauna

there are no less than three genera of honeysuckers (Ptilotus, Leptorms and

Myzomela) ; there is also alory (Vini). On the other hand, there are a kingfisher

(Halcyon), a thrush (Turdus), and several genera of pigeons, groups which are

at least as Oriental as they are Australian. Similarly, among the absentees

are a number of characteristic Australian birds, and others, the crows and the

hawks, which are of general distribution. It would, perhaps, be fair to say that

the avifauna of Samoa is very limited, and that certain widely spread families

are absent; that it has been derived from the west; that its origin is partly

from Asia, and partly from Australia.

Of REpriLEs, Samoa has four species of sea snake (Latecauda, three species ;

Pelamis, one species), but these are not likely to be of zoogeographical interest.

There is only one terrestrial snake, a boa (Engyrus bibront), found also in Tonga ;

no land snake is found to the east of Samoa and Tonga. Ten or eleven lizards

are recorded, about equally divided between the Geckonidae and Scincidae.

All the lizards have a wide distribution in Oceania, and the range of several

extends from the Moluccas to the Paumotu Islands. We do not know the

explanation of the wide distribution, but it is certainly clear that no lizards have

THE FAUNA AND FLORA. 23

reached Samoa except those which possessed the power of extending their dis-

tribution remarkably. There are no land tortoises or crocodiles in Samoa.

AMPHIBIA are absent, frogs extending eastwards through Melanesia to Fiji,

but not into Polynesia. :

No genuine fresh-water FisH occur in Samoan streams and swamps. The

fish which are abundant in these places are all clearly derivable from the sea ;

there are, for instance, gobies, and two species of Kuhlia, a genus of marine fish,

some species of which have entered fresh water. The marine vertebrates and

invertebrates of Samoa can probably give no clue to the zoogeographical pro-

blems, for in most groups of marine organisms great uniformity prevails through

the tropical Pacific, and very many forms are also widely spread in the Indian

Ocean.

The Prawns, so characteristic of Samoan mountain streams, may perhaps

be considered here. Our collection contained representatives of Palaemon,

Leander and Caridina. The first two are so nearly related to marine forms

that they do not show whether Samoa is or is not oceanic. Caridia is a member

of the Atyidae ; these prawns, as Dr. W. T. Calman tells me, are doubtless a

true and ancient fresh-water group. But the genus and some of the actual

species are so widely spread, that he is tempted to suppose that they must at

times enter the sea. In any case their distribution is anomalous, and does not

appear to throw any light on our problem.

It is generally admitted that the terrestrial MoLtusca give valuable informa-

tion about the ancient relations of a fauna. The most general paper on these

animals in the Pacific is by Pilsbry. He points out that Partula is widely spread

in Melanesia and Polynesia, and that it is an ancient generalized type, not found

elsewhere. On the other hand, many groups found widely spread in the world

(e.g. Helicidae and Arionidae) are absent, though members of these groups have

been able to colonize oceanic islands in other parts of the world. Throughout

Polynesia, and including Hawaiia, the snail fauna is remarkably uniform, though

it is so unlike that found in other parts of the globe. From these, and other

facts, Pilsbry concludes that there was once a continental mass, including all

of Polynesia, with Hawaiia; this continent broke up into smaller land areas

in middle Mesozoic times, and the fact that this event took place so early accounts

for the absence of mammals and other groups from Polynesia. In my opinion,

Pilsbry has been more successful than any other writer in making a case for the

former existence of a mid-Pacific continent, but I find it difficult to accept his

24 INSECTS OF SAMOA.

view, for it seems to conflict with our general knowledge of the fauna of the

area. Moreover Hedley, an authority on Mollusca and on Pacific faunas in

general, appears to have reached a conclusion different from Pilsbry’s. Hedley

points out that the land shell Placostylus is large and heavy, and that it is not

likely that it has crossed the sea. It is found in all Melanesia, cluding New

Caledonia and the Loyalty Islands ; also in Fiji; also in New Zealand. But it is

not known to occur in Samoa. This observation appears to support the view

that Samoa is oceanic, and to conflict with Pilsbry’s view, unless, indeed,

Pilsbry’s continent had already become a number of islands before Placostylus

reached its present home.

In the forests we commonly found NEmMerrEaNS. Our specimens have

been identified by Miss Hett as Geonemertes palaensis. She reports that they

belong to a species previously recorded from the Pelew Islands and Celebes.

The material from Samoa shows that the species has an enormous oceanic range,

and it seems probable that this may be explained by the fact that the natives

made long voyages 1n canoes, in which they carried great quantities of vegetables

(page 28). If this explanation is correct, then Geonemertes contributes nothing

to zoogeography. Jor a similar reason one would expect that little could be

learnt from earthworms, had a collection been made.

One may, perhaps, summarize our general knowledge of the Samoan fauna

(exclusive of the insects, to be discussed later) in the following terms :—

1. The fauna is that characteristic of ‘“‘ Oceanic ”’ islands, in the sense in

which the term was used by Darwin and by Wallace; there are no indigenous

land mammals (except bats), no amphibia, no freshwater fish; many widely

distributed animals and groups of animals are absent ; the proportion of endemic

species and genera is high ; there are no species of very high antiquity, or very

sreat morphological interest.

2. The fauna is derived from the west, and not from America.

3. The fauna is related to that of Asia and Malaya, at least as much as it is

to that of Australia. Wallace’s attribution of Polynesia to his “ Australian

Region ”’ is disputed.

It will be seen that the faunistic evidence is definitely opposed to the view

that Samoa is a relic of a former continental mass. Had it been so, it would

not have had an “‘ oceanic” fauna, and some relation would have been discovered

with the plants and animals of the American continent.

THE FAUNA AND FLORA. 25

FLORA.

On the coast of the Samoan islands one finds typical strand plants. Some

are low herbs, straggling over the sand, others are shrubs and trees: all alike

have a very wide range, and many of the species are known both from the Indian

and the Pacific Oceans (Plate 4, A). It is probable that all, or nearly all, these

plants have reached Samoa as floating seeds (see Guppy, vol. 2; Setchell, p. 18,

etc.). It is probable that there is an associated fauna of widely distributed

insects, but the point has hardly been investigated. The vegetation of all other

parts of Samoa is luxuriant, as the temperature is high and constant, and rain

falls abundantly at all seasons. Except where man has made clearings, the

islands are covered with a dense general covering of plants, which grow even

on the cliffs. As in other tropical rain forests, many sorts of trees grow, mixed

with one another and with shrubs, creepers and epiphytes (Plates 1 to 3, 5 and 6).

Above about 1,500 feet the island is frequently covered with cloud, so that pre-

cipitation is high and evaporation is low ; these conditions produce exceptional

luxuriance, and the mountain forests contain a great variety of epiphytic ferns,

mosses and liverworts. At first sight it was not easy to detect any seasonal

changes in the vegetation, which is evergreen, so far as its general effect goes.

But one soon found that particular species of plant and tree had definite flowering

seasons ; for instance, Hrythrina indica flowered in July, wherever it occurred ;

many other trees had equally definite seasons, so that the Honeypeckers and

Lories would be found congregated at blossom in some particular part of the

forest, and the Fruit Doves would be at work on some different species of tree,

which had been in flower a couple of months earlier. Setchell suggests that

these seasonal events may be due to temperature. This seems to me to be

improbable in view of the fact that the latter is nearly constant (page 14).

I venture to suggest that a more probable cause is the great difference in solar

radiant heat received at different seasons (page 13).

The flowering plants have been studied carefully, particularly on Upolu and

Tutuila ; over 800 species are known, of which more than 30 per cent. are

endemic to Samoa, or to one island in Samoa. The other land plants have been

less carefully collected, but 260 species of ferns, etc. (Pteridophytes), 395 mosses

and hepatics, 214 fungi and 184 lichens are already known; one is therefore

justified in saying that these groups form a high proportion of the total land

flora.

26 INSECTS OF SAMOA.

The flora of Melanesia and the greater part of Polynesia is derived from the

west, and is an extension of that of Malaya; except perhaps in Easter Island,

and along the extreme easterly fringe of Polynesia, there is no relationship with

the flora of America ; there is also no relationship with the peculiar flora of New

Zealand. In their flora, the islands of Samoa most nearly resemble Fiji and

Tonga ; the three appear to form a definite group, not closely like other Poly-

nesian archipelagos. But it is understood that the resemblances even to Fiji

and Tonga are not very great. Not only are more than 30 per cent. of the

flowering plants of Samoa endemic, but there are striking general peculiarities.

Setchell (page 28) mentions the absence of trees of the orders Compositae and

Lobelioideae, and the absence of all Pittosporaceae and Gymnosperms. Apart

from the endemicity, and the absence of these groups, Setchell calls attention

to the fact that many of the prevalent plants have small seeds, which render

dispersal by wind possible. Our knowledge of the flora is consistent with the

view that Samoa is an oceanic archipelago.

The principal authorities on the flora of Samoa are Rechinger and his

associates, Reinecke and Setchell. Setchell’s work is the most recent, and his

monograph includes a general summary on the vegetation of the group ;_he also

gives lists of introduced plants and weeds, and devotes very full attention to

the plants which are used by the Samoans ; on his work I have based this short

account,

THE PEOPLE.

The geologist has to study the Pacific without the aid of fossils or strata ;

the difficulties of the anthropologist are similar, for his subjects have left no relics

in flint, earthenware or metal. But it appears to be almost a matter of agree-

ment among anthropologists that the peoples of Melanesia and Polynesia came

from the west: they are emigrants from 8.H. Asia.* The evidence for this

view does not concern us, but it is interesting to discover certain zoological

facts which tend to confirm it. It is known that both Melanesians and Poly-

nesians kept domestic swine before the coming of the white man; the animals

were an important part of the food supply, and in parts of Oceania had also a

* The view is held in certain quarters that the civilization of America has been influenced

by Asia and by Egypt; it is interesting to observe that no support to this view can be found

in the fauna or flora, or in the useful plants of Polynesia. The cultivated plants of Tropical

America, for instance Paw Paw and Manioc, were absent from Samoa until introduced by

Europeans, ae)

THE PEOPLE. 27

great value in ritual. These aboriginal pigs no longer exist as a pure stock, for

HKuropean pigs have been imported at intervals for more than a century. But

the connection with Asia is suggested (not proved) by the discovery of the

Nematode Bourgelatia diducta in the intestines of pigs in Mauke, Cook Islands,

and in Tonga ; this worm was previously recorded only from Annam (Schwartz).

The lice collected on pigs both in Samoa and the New Hebrides suggest the same

conclusion; they were determined by Waterston as Haematopinus suis var.

adventicius, a variety described by Neumann from wild swine in 8.E. Asia. The

helminthic parasites of man are much less easily explained. The facts are very

well known, owing to the work of Lambert; he has shown that in Papua, and

wherever he has worked in Melanesia and Polynesia, the people are infected by

the whipworm (Trichuris trichuris) and by Necator americanus, a relative of the

hook-worm. On the other hand, they do not harbour the round-worm (Ascaris

lumbricordes), nor the hook-worm (Ancylostoma duodenale), except where these

parasites have been recently introduced by Asiatic labourers. The evidence

relating to human migration and history, which may be derived from Ancylostoma

and Necator, is reviewed by Darling. He shows that Necaior is characteristic

of tropical Africa, and of Papua and Oceania. Ancylostoma is prevalent in

Europe, N. Africa and Asia. At first sight, then, the evidence to be derived

from these two worms appears to conflict with the view that the people of

Oceania are Asiatics. But this is not necessarily the case, for the people of South

India are mainly infested with Necator ; in Java this worm is found in pure

culture in remote places in the hills ; in other places, where a part of the native

race was derived from India in historic times, the prevalent parasite is Ancy-

lostoma. One may, therefore, say that the evidence to be derived from these

worms is not inconsistent with the Asiatic origin of the peoples under discussion ;

the absence of Ascaris lumbricoides, and the fact that when it is introduced it

quickly becomes common, are at present unexplained. The complete absence

of Cestodes and of Trichinella spiralis from a human population intimately

associated with pigs and rats is also anomalous.

Let us accept it, then, that the people came out of Asia, travelling eastwards

and leaving many plants and animals behind them as they did so. By the time

they arrived in Samoa, they had left betel and sago, Anopheles and Plasmodium

far behind them. But they brought with them many cultivated plants, and also

dogs, pigs and cats; I have already mentioned the small rat (page 19), the

present distribution of which suggests that it was carried by man. Samoa, so

28 INSECTS OF SAMOA. —

central though so isolated, became one of their principal centres of dispersal.

Indeed, the name Savai’i is equivalent to “ Hawaiki,” the traditional home of

the Maories of New Zealand. Though much of the ancient culture disappeared

more than a century ago, enough has been preserved to give us a fair general

knowledge of it. The people were seafarers, with a traditional system of naviga-

tion ; they put to sea in great canoes, which carried scores of people, and supplies

of food for many days ; their commerce and their raids frequently carried them

many hundreds of miles across the open ocean. Beyond this small canoes

must frequently have been blown away from home, as they are to this day ;

these would be carried down wind, that is to say, back towards Asia, so that

coming and going was much more general throughout Polynesia than one

would have supposed. As I have recently published a number of facts about

native voyages (Buxton, 1928, p. 99), no more need be said here, but the fact

that these voyages occurred, and that great quantities of food and other materials

were transported, must not be forgotten; the great canoes must have been

potent in carrying insects and small animals, also weeds, from one archipelago to

another.

The ancient Samoans had many needs, and knew how to meet them ; they

were, in fact, civilized. They were far from being naked simple savages, chewing

roots and hiding in caves. Though they knew nothing of clay, flint, or metal,

they employed vegetable products in a great variety of ways. They built, and

they still build, magnificent houses, choosing particular timbers for lightness,

others for strength or elasticity, binding them together with fibres and closing

the whole with a thick thatch, and matting sides (Plate 4, C). They made and

sailed the great canoes to which we have referred. They were enthusiastic

gardeners, with a taste for flowers. They feasted on taro (root of Colocasia),

bread fruit, yams, sweet potatoes, coconuts, and many other fruits, nuts and

roots, some of which were indigenous, others brought from overseas ; they had

their sweets and sauces, and employed particular sorts of leaf for wrapping the

food that was to be put in the oven. They cultivated Kava, from which they

made a ceremonial drink. They fished with lines and nets and traps. They

had their clothes for work, and for occasions of ceremony ; they adorned them-

selves with garlands, anklets and necklaces; they gave much time and study

to the compounding and use of unguents, pigments and cosmetics. In these

and very many other ways, they made use of the vegetable kingdom. ‘The sub-

ject, which is one of great interest, may be followed further in the works of

THE PEOPLE. 29

Powell, Reinecke, Kramer and Setchell. When we remember that many of

the useful plants were cultivated and carried about the Pacific in the voyages,

we shall realize what opportunities there must have been for the carriage of

insects, worms, molluscs, etc., from one archipelago to another. I hope that

when the results of our entomological studies are summarized, | may publish

lists of some of the insects which apparently owe their distribution to this cause.

The best general account of the Samoan people is the work of Kramer.

It is fitting to conclude these remarks with a few words about the penetration

of Europeans into Samoa. So far as we know, until the year 1800 Europeans

had only paid four short visits to our archipelago, but in the early years of the

nineteenth century there were a few white residents, most of whom had run away

from ships. In 1830 the first missionary, John Williams, landed for a few days ;

he left some Tahitian teachers and returned in 1832. His arrival is of interest

to us because he travelled very widely, and wherever he went he introduced new

domestic animals and cultivated plants ; he also hurried forward the introduction

of Western ideas and awoke a demand for foreign products. These needs were

soon met, and increased, by ships and traders. For various reasons the super-

ficial Kuropeanization of Samoa proceeded rapidly from 1830 to 1850. In 1850

European Governments became directly interested in Samoa, though it was not

until 1899 that the islands were divided between Germany and the United

States. |

As regards the fauna and flora, the entry of Europe upon the scene has had

many different results. A very great variety of exotic flowers and fruits is now

grown, though none is important commercially ; the surface of the islands is so

rough that no organized development of tropical agriculture seems probable ;

there are considerable areas of turf, which consists mainly of foreign grasses

and other plants. Foreign timber and foreign fruit is commonly seen in Apia.

Ships containing sheep and cattle have called, times without number, and are

probably responsible for the presence of dung-breeding flies, etc. On the other

hand, as the people eat imported food and make use of Huropean fabrics,

metals, etc., they resort less and less to the forest for the innumerable products

which their ancestors used, and the arts of fowling and fishing are rapidly dis-

appearing. The effect of the foreigners upon the Samoan fauna is therefore

complex, particularly so in view of the difficulty of deciding whether a particular

insect or plant was brought in by the white man, or centuries ago in a Polynesian

canoe. Taking it all in all, it appeared to me that the total effect of the intro-

30 INSECTS OF SAMOA.

duced plants and animals was very little; the archipelago is almost entirely

covered with virgin forest, containing a wealth of native and endemic forms

of life.

REFERENCES.

ANGENHEISTER, G. (1924). A summary of the meteorological observations of the Samoan

Observatory (1890-1920). (Edited by E. Marsden and D. M. Y. Somerville.) Wellington.

Buxton, P. A. (1926). The radiation integrator in vacuo, an instrument for the study of radiant

heat received from the sun. Journ. Hyg., vol. 25, pp. 285-294.

Buxton, P. A., and Hopxins, G. H. E. (1927). Researches in Polynesia and Melanesia. Parts

iv, No. 1 Memoir Series, Lond. Sch. Hyg. and Trop. Med.

Buxton, P. A. (1928). Researches in Polynesia and Melanesia, Parts v-vii. No. 2 Memour

Series, Lond. Sch. Hyg. and Trop. Med.

Dany, R. (1916). Petrography of the Pacific Islands. Bull. Geol. Soc. Amer., vol. 27, pp. 325-344.

Dany, R. (1924). The geology of American Samoa. Papers from Dept. Marine Biol., Carnegie

Institute, Washington, vol. 19, pp. 93-143.

Daruine, 8. T. (1925). Comparative helminthology as an aid in the solution of ethnological

problems. Amer. Journ. Trop. Med., vol. 5, pp. 323-337.

Davis, W. M. (1928). The Coral Reef Problem. Amer. Geograph. Soc. Spec. Publication No. 9.

Grecory, J. W. (1930). The geological history of the Pacific Ocean. Nature, vol. 125, pp.

750-751.

Guppy, H. B. (1906). Observations of a naturalist in the Pacific between 1896 and 1899.

New York.

Hepury, ©. (1899). A Zoogeographic Scheme for the Mid-Pacific. Proc. Linn. Soc. N.S.

Wales, vol. 24, pp. 391-417.

Hert, M. L. (1927). On some land Nemerteans from Upolu Island (Samoa), with notes on the

genus Greonemertes. Proc. Zool. Soc. Lond., 1927, pp. 987-997.

HotpHavs, K. (1929). Die geographische Verbreitung der Insekten. Handb. der Entomologie :

Schréder, Band 2, pp. 592-1058.

Iuos, A. D. (1930). A General Text-book of Entomology, 2nd Ed. London.

Kramer, A. (1902). Die Samoa-Inseln. Stuttgart.

LamBert, 8S. M, (1928). Medical conditions in the South Pacific. Med. Journ. Australia, vol. 2,

pp. 362-378.

MarsHatu, P. (1908). Oceania. Handbuch der Regionalen Geologie: Steinmann, Band 7,

Heft 2.

Mayor, A. G. (1924). Rose Atoll, American Samoa. Papers from Dept. Marine Biol. Carnegie

Institution of Washington, vol. 19, pp. 73-79.

Minter, G. 8. (1924). The characters and probable history of the Hawaiian Rat. Bernice P.

Bishop Museum, Bull. 14.

Murpny, R. C., and Marruews, G. M. (1928). Birds collected during the Whitney South Sea

Expedition. Amer. Mus. Novitates, No. 337.

Perkins, R. C. L. (1913). Introduction, being a Review of the Land-Fauna of Hawaiia. Fauna

Hawaiiensis, vol. 1, part 6.

PowE LL, T. (1868). On various Samoan plants and their vernacular names. Journ. Bot., vol. 6,

pp- 278-285, 342-347, 355-370.

Pinspry, H. A. (1900). The genesis of Mid-Pacific Faunas. Proc. Acad. Nat. Sci. Philad., 1900,

pp. 568-581.

REFERENCES. 3l

REcHINGER, K. (1908-1914). Botanische und zoologische Ergebnisse einer Wissenschaftlichen

Forschungsreise nach den Samoa-Inseln, dem Neuguinea-Archipel und den Salomons-Inseln.

Denkschr. der K. Akad. der Wissenschaften, Math. und Naturw. Klasse, Bd. 81, pp. 197-317 ;

Bd. 84, pp. 385-562; Bd. 85, pp. 175-482; Bd. 88, pp. 1-65; Bd. 89, pp. 443-708; Bd.

91, pp. 139-213. (Edited by Rechinger ; special articles by many authors.)

REINECEE, F’. (1898). Die Flora der Samoa-Inseln. Botan. Jahrb., Bd. 23, pp. 237-368 ; Bd. 25,

pp. 578-708.

SETCHELL, W. A. (1924). American Samoa; Part 1, Vegetation of Tutuila Island. Part 2,

Ethnobotany of the Samoans. Papers from Dept. Marine Biol. Carnegie Institution of

Washington, vol. 20, pp. 1i—vi, and pp. 1-224.

Scuwartz, B. (1927). Proc. Helmin. Soc., in Journ. Parasitol., vol. 13, p. 83.

Tuomas, O. (1895). Proc. Zool. Soc. London, p. 338.

Tomson, A. (1927). Solar Radiation Observations at Apia, Samoa. Monthly Weather Review,

vol. 55, pp. 266-268.

VisHER, 8. 8., and Hopes, D. (1925). Australian Hurricanes and Related Storms, with an Appen-

dix on Hurricanes in the South Pacific. Commonw. of Austral, Bureau of Meteorol. Bull. 16.

LIST OF TEXT-FIGURES.

Text-figure 1. Map of the South-West Pacific Ocean.

Text-figure 2, Map of Samoa, indicating places where collections were made.

LIST OF PLATES.

Plate 1. Gorge near Malololelei, Upolu, at about 1,800 feet above sea-level.

Plate 2. River running through ravine, about two miles east of Vailima, at about 600 feet above

sea-level.

Plate 3. Waterfall and torrent near Malololelei, Upolu, at about 1,800 feet above sea-level.

Plate 4. A. White coral sand, strand vegetation (Ipomaea), and coconuts, near Apia. B. Lava

tunnel, near Malololelei, about 2,000 feet. C. Village in Savaii, with breadfruit trees,

and turf of foreign grasses and weeds.

Plate 5. Rain forest near Malololelei, about 1,800 feet.

Plate 6. Forest: with palms and ferns, near Malololelei, about 1,800 feet.

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BRIT. MUS. (NAT. HIST. INSECTS OF SAMOA.

PLATE 1.

PLATE LI.

Gorge near Malololelei, Upolu, at about 1,800 feet above sea-level.

BRIT. MUS. (NAT. HIST. INSECTS CF SAMOA.

PART IX. PLATE I.

PLATE I.

River running through ravine, about two miles east of Vailima, at about 600 feet above sea-level.

BRIT. MUS. (NAT. HIST.) INSECTS OF SAMOA.

PART IX. PLATE Il.

PLATE III.

Waterfall and torrent near Malololelei, Upolu, at about 1,800 feet above sea-level.

*X1 LYWd

‘VONVS AO SLOASNI (LSIH “LVN) ‘SOW ‘LINa

PLATE IV.

A. White coral sand, strand vegetation (Ipomaea), and coconuts, near Apia. 8. Lava tunnel,

near Malololelei, about 2,000 feet. C. Village in Savaii, with breadfruit trees, and turf of

foreign grasses and weeds.

BRIT. MUS. (NAT. HIST.) INSECTS OF SAMOA.

PART IX. C PLATE IV.

PLATE V.

Rain forest near Malololelei, about 1,800 feet.

INSECTS OF SAMOA.

BRIT. MUS. (NAT. HIST.)

eI

~

~

PLATE V,

PART IX,

PLATE VI.

Forest with palms and ferns, near Malololelei, about 1,800 feet.

BRIT. MUS. (NAT. HIST.) INSECTS OF SAMOA.

PART IX. PLATE VI.

INSECTS OF SAMOA

AND OTHER SAMOAN TERRESTRIAL

ARTHROPODA

LIST OF PARTS AND SYSTEM OF PUBLICATION -—

Part 1. Orthoptera and Dermaptera.

II. Hemiptera.

» 111. Lepidoptera.

»» IV. Coleoptera.

» Vv. Hymenoptera.

VI. Diptera.

',, WII. Other Orders of Insects.

»» WII]. ‘Terrestrial Arthropoda other than Insects.

»» LX. Summary and Index.

The work is published at intervals in the form of numbered fascicles.

Although individual fascicles may contain contributions by more than one

author, each fascicle is so arranged as to form an integral portion of one or

other of the Parts specified above.

List of Fascicles eee to 22nd November, 1930:—

eee eres arid) other Sanioan Verresivial Arthropoda. Maps | and Daie Issued.

2 (inenvelope). 1927, 4to. 6d. 26th February, 1927.

Part I. OrTHopTera AND DERMAPTERA.

Fase. 1. Dermaptera. By Dr. Alfredo Borelli. Pp. 1-8. 1928, 4to. Is. 28th July, 1928.

Fasc. 2. Orthoptera. By Dr. L. Chopard. 5] text-figures. Pp. 9-58. 1929, 4tos 5s. 26th January, 1929.

Part I]. HeEmIpTera.

Fasc. 1. Fulgoroidea. By F. Muir. 25 text-figures. Bayle (Chermide). By

Prof. D. L. Crawford. 4 text-figures. Coccide, Aphidide and Aleyrodide.

By F. Laing, M.A., B.Sc. 3 text-figures. Pp. 1-45. 1927, 4to. 2s. 6d. 25th June, 1927.

Fasc. 2. Cercopide. By V. Lallemand, M.D. 10 text-figures. Cicadide. By

ast Myers, Sc.D. 22 text-figures. " Aquatic and Sa Heteroptera. a

y Prof. Teiso Esaki. 6 text-figures. Pp. 47-80. 1928, 4to. 2s. 6d. 23rd June, 1928.

Fasc. 3. Heteropt By W.E. China, B.A. (Cantab 28 text-fi ;

Pp. 8l- 162, 1930, 4to. 3s. i Eos ee Ith July, 1930.

~ Part III. Leprpoptera.

Fasc. 1. Butterflies of Sa d hb: Isl By G.H. E.

FE oN eT tet eons Ed ane eee N27 tte de 9th April, 1927.

Face 2) Micro LLeonloptcra? By Bayard’ Mayne’ BIAS ERS: Pol Qe-116

OAs Ja Ge RT Ne : 28th May, 1927.

Focal 3. Gooner: By ntis BRP REG N? texte a hee

950 EOI dee ea Fee eee arn iVfoch. 1928.

List of Fascicles issued to 22nd November, 1930 (continued) :—

Part IV. CoLEopTerRA.

Fasc. 1. Carabide. By H. E. eae fi ene Dytiscide. By A.

immermann. 2 een Staphylinide. M. Cameron, MB. 2 text-

gures. Hydrophilide. bi ymont. Beane Clavicornia and

Lamellicornia. By G. J. eee 13 text-figures. Pp. 1-66. 1927, 4to. 3s.

Fasc. 2. Heteromera, Bostrychoidea, eee a and Buprestide. By K.G.

Blair, B.Sc. text-figures. Elateride. . van Zwaluwenberg, 10

text-figures. Meee (enencaue #). by EH Mane Cerambycide. By

Chr. ane “1 plate: Brenthide. By R. Kleine. 4 text-figures.

AuMbebo By oak dey BED A oe cues Broterhinidee, By

RCL: te. BY DSc., ¥.R.S. Pp. 67-174. 1928; 4to. 5s.

Fasc. 3.. Throscide. By K. G. Blair, B.Sc. 1 text-figure. Chejtsmclide:

By S. Maulik, M.A. 18 text-figures. Pp. 175-215. 1929, 4to. 2s. 6d.

Fasc. 4. Platypodidae and Scol pane, By C. F. C. Beeson, D.Sc. 13 text-

figures. Pp. 217-248. 1929, 2s. 6d.

Part V. HYMENOPTERA.

Fasc. |. Apoidea, Sphecoidea, and Vespoidea. Ee R. C. L. Perkins, ee

F.R.S., and_L. Evelyn Cheesman, F.E.S., F.Z.S. 12 text ve Larride.

By Francis X. Williams. 12 text-figures. Formicide. F. Santschi.

9 text-figures. Pp. 1-58. 1928; 4to. 5s.

Part VI. DIPTERA.

Fasc. 1. Streblide and Nycteribiide. By L.Falcoz. 7 text-figures. Hippo-

boscide. By G.F. Ferris. 6 text-figures. Pp. 1-21. 1927, 4to. 2s. 6d.

Fase. 2. ene ByF.W. Edwards, M.A. 20text-figures. Cecidomyiine.

By H. F. Barnes, BA, PhD. 4text-fgures.. Pp. 23-108, 1928, Ato, 5a.

Fase. 3. SEmamintie. Tabanide and Miers By Gertrude Ricardo. 6 text-

figures. Larve of Stratiom lide. P. A: Buxton, M.A. 2 text-figures.

Dolichopodide. By C Cee, oh. 8 text-figures. BR Nl By

P. A. Buxton, M.A. c5 text-figures. NMuseides Malloch.

Pp. 109-175. "1929, 4to. 5s.

te ue oe ididae ea Pi Ete ae J. Collin. _7 text-figures.

Syrphidae. Bar Frank M. Hull 2 text-figures. ranes e (Heteroneuridae)

and Sspromyzide, By R. Mallock’ 6 text-figures. Pp. 177-213. 1929,

to. 4s. Od.

Fasc. 5. Ortalidae. By J. R. Malloch. 6 text-figures. Calliphoridae. By

J.R. Malloch. Pp. 215-237. 1930, 4to. 2s.

Fasc. 6. Lonchaeidae, Chloropidae and Piophilidae. By J. R. Malloch. 3

text-figures. Pp. 239-251. 1930, 4to. Is.

Part VII. Orner Orpers or INsEcTs.

Fasc. 1. Isoptera: F; ca Galea By Gerald F. Hill. _ 14 text-figures and

| plate. Odonata. By Lt.-Col. @ fae L.MS., F.E.S. 5 text-figures.

Pp. 1-44. 1927, 4to. 2s. 6d.

Fasc. 2. Plectoptera. By a ids Tillyard, Ear Dane eee and J. A.

Thysanoptera.

Lestage. 2 text-figures. Siphonaptera.

gees Lhe ‘Pp. 43-76. 1928, dto.

By Richard S. Bagnall, F.R

2s. 6d.

iM4 . Burton, MHA By anne, DSc. 2 text-figures. Anoplura. By |

Buxton, tichoptera. y Martin E. Mosely. 1 figure.

SG tdeedeng By DN hen Beeen 1 text-figure and 2 plete Apterygota.

By George H. Cacunter, 0. Sc. 32text-figures. Pp.77-I1 1928, 4to. 2s. 6d.

Part VIII. TerrestrR1AL ARTHROPODA OTHER THAN INSECTS.

Fasc. 1. Isopoda Hes: By Harold G. Jackson, D.Sc. 2 plates. Scor-

pionoidea. y Buxton, M.A. Pseudo-scorpiones. By A. Kastner.

ci Da Acarina. By Stanley Hirst. 2 text-figures. Pp. 1-27. 1927,

to .

Fasc, 2. Myriopoden (Myriopoda). By C. Attems. 4 text-figures. Araignées

(Araneida), By Dr. Lucien Berland. 79 text-figures. Pp. 29-78. 1929, 4to. 2s. 6d.

Part IX. Summary AND INDEX.

Fasc. |. Description of the Environment. By P. A. Buxton, M.R.CS. 2

text-figures and 6 plates. Pp. 1-31. 1930, Ato. 2s. 6d.

Date Issued.

19th December; 1927.

25th February, 1928.

23rd February, 1929.

22nd June, 1929.

25th February, 1928.

23rd July, 1927. :

23rd June, 1928. —

11th May, 1929.

27th July, 1929.

22nd March, 1930.

22nd November, 1930.

28th May, 1927.

23rd June, 1928.

28th July, 1928.

23rd July, 1927. ig i

20nd June, 19200 sm

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