INSECTS OF SAMOA

AND OTHER SAMOAN Eee as

ARTHROPODA . ae

Although a monograph, or series age 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 an 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 material of the groups

concerned in both the Bntish Museum (Natural History) and (by courtesy of 3

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

lt is not intended that contributors to the text shall be cones tothe —

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. | 4

The work is divided into eight ‘ ‘ Parts” (see p. 3 of wrapper), erate

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 work it is intended to issue a general survey, summarising the whole

and drawing from i it such conclusions as may be warranted.

A list of Fascicles already eh will be found on the a of thie wrapper.

E. E. AUSTEN,

Keeper of Entomology.

British Museum (Naturat History), on

CromweLi Roan, $.W.7. . NG | ae

INSECTS OF SAMOA

AND OTHER SAMOAN TERRESTRIAL

ARTHROPODA —

Although a monograph, or series Ae papers, dealing coumprckensaeny with —

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

- 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 an account of the Insects and other — P

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 Schoo! 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 material of the groups

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

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

lt is not intended that contributors to the text shall be conened 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. a

The work is Giaed into eight “ Parts” (see p. 3 of a Sul

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 work it is intended to issue a general survey, summarising the whole

and drawing from it such conclusions as may be warranted.

A list of Fascicles already issued will be found on the ae of ee wrapper.

Ee oh ‘AUSTEN,

Keeper of Entomology. x

British Museum (Natura History), Sih +

CromweLt Roan, $.W.7. we

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ENSE OCS OF SAMOA

Part IV. Fasc. 3

THROSCIDAE

By K. G. Buatr, B.Sc.

(With 1 Text-figure.)

1. Drapetes samoensis, sp. n.

Elongate elliptical, black, nitid, rather sparsely punctate and setose.

Head rather narrower than anterior margin of prothorax ; antennae with

basal joint elongate, curved, testaceous ; second and third joints small; fourth

to tenth joints strongly produced on inner side ;

last joint subpyriform. Thorax slightly wider

than long, widest at base, thence somewhat

sinuately narrowed to apex; anterior angles

rounded, deflexed, moderately prominent, tinged

with flavous in some examples ; posterior angles

not carinate, acute, backwardly projecting, closely

applied to shoulders of elytra, lateral margin

concealed from above by lateral convexity of

disc; base biemarginate with a smaller median

emargination before scutellum; disc strongly

but sparsely punctured anteriorly, basal quarter

slightly depressed and more finely and closely

punctured, leaving a narrow median elevated m,. 0 ae. 1.—_Dr apeiea samoenets

area devoid of punctures; each puncture giving sp. 0.

rise to a long, curved, cinereous hair, these hairs

directed towards middle line on anterior portion of disc, directed obliquely

forwards and inwards on inner part of basal depressed area, and forwards and

Iv. 3 175 1

176 INSECTS OF SAMOA.

outwards near posterior angles. Scutellum rather large, subcircular, finely

and closely punctate, with pubescence sloping backwards. LElytra widest at

shoulders, gradually narrowed posteriorly, with the apices broadly rounded ; disc

punctured much as fore part of thorax, a regular row of backwardly directed

setae on either side of suture, leaving a narrow sutural space devoid of setae ;

remainder of pubescence directed obliquely backwards and outwards.

Length, 4 mim.

Upolu: Vailima, 1., 1x.1925 ; Malololelei, iv.1924 ; vi1.1925 (6 examples).

Allied to D. jansont Bonv., of which the type locality is Batchian, though it

has also been found in Borneo, Singapore, and the Philippine Islands. The

latter species, however, has the antennae entirely black, the thorax more

sharply narrowed and more coarsely punctate, the punctures being larger at the

base than towards the apex, and the pubescence of both thorax and elytra

differently disposed.

Text-fig. 1. Drapetes samoensis, sp. 0.

CHRYSOMELIDAE; WITH A NOTE ON THE COMPARATIVE

ANATOMY OF SOME HALTICINE TIBIAE

By S. Mautuik, M.A., Canras., F.E.S., F.Z.S.

(With 18 Text-figures.)

THE following beetles of the Family Chrysomelidae occur in the Samoan Islands :

—

Subfamily CRyPTOCEPHALINAE. 1. Aprionota lucida, gen. et sp. nov.

. Pycnophthalma tutuilana, gen. et sp. nov.

. Stygnobia aenescens, sp. nov.

te cauta Weise

ss varvabilis, sp. nov.

a minuta, sp. Nov.

. Rhyparida subaenercollis Fairmaire.

. Siethotes rufonigra, sp. nov.

és CHRYSOMELINAE . 9. Plagiodera samoana, sp. nov.

a GALERUCINAE . 10. Aulacophora similis Olivier.

3 quadrimaculata F.

12. 1 nigrobrunnea, sp. nov.

13. Plesistia brunnea, gen. et sp. nov.

3 HALTICINAE . . 14. Nesohaltica nigra, gen. et sp. nov.

15. Sphaecrophyma insularum, sp. nov.

tis HIsPINAE ; . 16. Promecotheca reichei Baly.

Hs CASSIDINAE . . 17. Cassida strigula Montrouzier.

x KUMOLPINAE .

COA Oe wb

Remarks about variation, geographical distribution, morphology and other

interesting points have been made in the body of the paper, but can be sum-

marised as follows :

(1) The species that are apparently eae and confined to these islands

have Australasian affinities.

(2) Some species of wider distribution also occur in these islands.

(3) Some species have evidently been introduced with agricultural

commodities.

(4) A general idea concerning variation in island faunas is formulated on

p. 191.

(5) Of the sixteen subfamilies of Chrysomelidae, seven are represented in

the collections dealt with in the present paper.

177

178 INSECTS OF SAMOA.

(6) The seventeen species here recorded include representatives of four new

genera, eleven new and six previously described species.

(7) One species (Promecotheca reicher Baly) has been recorded as a pest of

the coconut palm, though it was rare in 1924, 1925.

I wish to record my sincere thanks to Messrs. W. H. T. Tams and K. G.

Blair of the British Museum (Natural History), Mr. G. E. Bryant of the Imperial

Bureau of Entomology, Dr. Walther Horn of Berlin, Dr. Franz Heikertinger of

Vienna, and Dr. J. B. Corporaal of Amsterdam, for assistance in my study. In

addition, I am much indebted to Mr. A. J. EK. Terzi, who has made the drawings

for the text-figures.

CRYPTOCEPHALINAE.

Aprionota, gen. nov.

Body ovate, not hairy above. Head deeply imbedded in the prothorax.

Antennae fairly long, extending nearly to the middle of the body, eleven-seg-

mented, six apical segments thickened but not formed into a club. LHyes

emarginate near the roots of the antennae. Prothorax with the base not

margined, and with the median portion produced into an acute lobe ; the basal

edge without serrations. Scutellwm small, visible from above, not hidden by

the median lobe of the prothorax and not sloping. Hlytra punctate-striate.

Under side: intercoxal process of prosternum almost quadrate, broad, with the

surface rough and the sides margined ; front coxal cavities rounded. Bilobed

seoment of the tarsi small, claw segment projecting a little beyond the bilobed

seoment ; claws appendiculate.

Relationship.—In the form of the body and general facies the genotype of

the present new genus resembles Detropidus and the allied genera; and these

include a considerable number of species belonging to the Australian region.

The present genus differs from Ditropidus in not possessing an antennal club, and

in not having serrations on the posterior edge of the pronotum. On the other

hand the species now to be described cannot find a place in the genus Crypto-

cephalus, because the former has the median portion of the pronotum produced

into a lobe and the scutellum small, though not hidden from view by the median

lobe, and not in a sloping position.

Genotype : Aprionota lucida Maulik.

Range : Samoa.

CHRYSOMELIDAE. 179

1. Aprionota lucida, sp. nov. (Text-fig. 1).

Body narrowed in front and more so posteriorly. General colour shining

black, sometimes slightly diluted with dark red-brown ; five basal segments

of antennae brown, tinged with blackish ; legs similarly coloured, in some cases

brown predominating, in others blackish colour more evident.

Head with impunctate vertex. Eyes approximated, separated by a thin

strip. First segment of antennae long and club-shaped, second small rounded,

third and fourth equal, each being

shorter than fifth, sixth thicker and

longer than fifth, seventh to tenth

about equal to each other, eleventh

somewhat smaller, ovate and blunt.

Prothorax narrowed in front, with

somewhat convex margin; sloping

at each side; lateral edge margined ;

upper surface smooth, almost im-

punctate, or seen under a high power

very sparsely punctate. Scutellum

small, ovate, flat, smooth and im-

punctate. Hlytra not broader at base

than prothorax. Humerus not con-

vex nor prominent. On each elytron

eleven longitudinal regular rows of

punctures, including a scutellar and

an extreme marginal row ; intervals

between rows appearing raised on

lateral and apical areas, and the rows Text-Fic. 1.—Aprionota lucida, sp. n. X 24.

themselves appearing deeply im-

bedded in channels; rows meeting in pairs on apical area, and, at least those

on discal area, not parallel to suture but inclined to it at an acute angle ;

surface of intervals smooth and impunctate. Under side: sparsely hairy,

abdominal sternites more hairy; female with a deep fossa in middle of

penultimate visible sternite.

Length, 99 24 mm.; gg 2 mm.

Upolu: Malololelei, 2,000 ft., vi.1924, 4 examples; 22.x1.1924 (type),

4 examples, one of which is mounted in balsam,

180 INSECTS OF SAMOA.

Tutuila : 760-900 {t., 1v.1918 (Kellers), 1 9 example.

Type in British Museum.

Described from nine examples.

Pycnophthalma, gen. nov.

Body ovate. Hyes large, touching each other on upper side of head. Near

the root of each antenna a certain area is without the facets of the eye, so that

there is a deep emargination. Antennae eleven-segmented, extending almost to

middle of body, the six apical segments thickened but not formed into a club.

Prothorax narrowed in front; base not margined, edge with serrations, part

opposite scutellum produced into a lobe which ends in an acute point; sides

margined ; anterior and posterior angles rounded. Scutellum visible from above,

narrow, oblong with rounded apex and base fitting against point of prothoracic

lobe. Hlytra not broader at base than prothorax, punctate-striate, longitudinal

series of punctures being deeply imbedded in channels. The striae appear, at

least on discal area, to be inclined to the suture, 7.e. they are not parallel to it.

Viewed from above, pygidium not exposed. Under side: intercoxal process of

prosternum almost quadrate or slightly longer than broad, with surface rough

and coarsely pitted, sides margined, and posterior edge widely arched.

Epipleurae of elytra broader at base and narrowed from middle to apex. Legs

fairly stout, not long, so that when withdrawn they are not visible from above ;

claw segments of tarsi projecting a little beyond bilobed segment; claws

appendiculate.

Genotype : Pycnophthalma tutwilana Maulik.

Range : Samoa.

Relationship—tIn the form of the body and the character of the eyes

Pycnophthalma resembles the genus Caenobius, which was erected by Suffrian

in 1857 for an African insect. Since then, owing to the eye character, many

species found in Australia, New Guinea, the Fiji Is., Japan, the Philippine Is.,

the Malay Peninsula, India, and Africa have been included in Caenobius.

The species do not seem to form a homogeneous group, and some of them,

particularly the African genotype, differ in many respects from the type

species of the present new genus. In all probability several species, especially

such as occur in the Australian Region, will find a more suitable place in

Pycnophthalma,

CHRYSOMELIDAE. 181

2. Pycnophthalma tutuilana, sp. nov. (Text-fig. 2).

Body small. Upper side greenish, under side shining pitch-black, legs and

antennae yellow-brown, six apical segments of antennae fuscous.

Head deeply imbedded in prothorax, vertex invisible from above. Hyes

very large, occupying greater portion of head. Clypeus slightly convex, punctate,

each puncture bearing a little hair. First segment of antennae long, thickened

and club-shaped ; second small, rounded; third, fourth, and fifth segments

slender and about equal to each other in length; sixth and seventh equal ;

eighth to eleventh segments equal to each other, the last blunt, not pointed ;

six apical segments more hairy. Prothorax: front edge together with front

edge of prosternum forming a complete

circle surrounding head; anteriorly and s@®7°°Ssa_ Pee AG ic

laterally a deep fossa; upper surface

closely punctate ; punctures on discal area

appearing somewhat elongate and, although =

without any definite arrangement, tending \

to converge towards apex ; on lateral area

punctures are coarser and coalesce with

each other. Scutellwm smooth, impunctate

and appearing imbedded in thickened

elytral margin. Flytra: anterior margin

thickened ; each elytron with ten longi-

tudinal rows of punctures placed in deeply

excavated channels ; counting from suture

and including scutellar row, the sixth row, Trxt-FIG. 2.—Pycnophthalma tutuilana,

which is internal to humerus, is very deeply sp.n. xX 30.

excavated ; intervals between rows raised,

fairly broad, very minutely punctate and bearing very fine hairs; the rows of

punctures meet in pairs on apical area. Under side: metasternum with median

longitudinal impression. Anterior and middle coxal cavities rounded. Abdominal

sternites finely and closely punctate, bearing very fine scattered whitish hairs.

Other structures as stated under generic diagnosis.

Length, 2 ram.

Tutuila: Pago Pago, 10.1x.1923 (Swezey and Wilder), type.

Type in the Bishop Museum, Honolulu.

Described from one example.

ooo eH

182 INSECTS OF SAMOA.

HUMOLPINAE.

Stygnobia Weise.

Stygnobia Weise, Archiv fiir Naturgesch. \xxxviii, Abt. A., Heft 10, pp. 154, 155, 1922.

This genus was founded by Weise for three specimens collected in Upolu,

in March, 1913, by Dr. K. Friederichs. Two of these were described as repre-

senting one species, and the third as belonging to another. Through the courtesy

of Dr. Walther Horn, of Berlin, I have been able to make an examination of

these types, as a result of which, and in view of the fact that I have before me

a large number of individuals of four species of this genus, a modification of the

generic concept is necessary. I therefore redescribe the genus as follows :

Body oblong, ovate, somewhat convex, completely covered with hairs,

although on the under side the hairs are very fine and sparse. Antennae eleven-

segmented, the fourth segment being the longest. Prothorax broader than long,

somewhat narrowed in front, sides marginate. SHlytra confusedly punctate.

Under side: prosternum narrowed between coxae. Anterior margin of pro-

thoracic episternum subconcave. Legs long, slender ; middle and hind tibiae

emarginate at apex; claws divided into two branches, the inner smaller than

the outer.

Genotype : Stygnobra cauta Weise.

Range: Apparently confined to the Samoan Islands.

3. Stygnobia aenescens, sp. nov. (Text-fig. 3).

Body subnitid, oblong, ovate, broadest at base of elytra and very slightly

narrowing towards apex ; general colour very dark pitch brown, almost black,

with bronzy reflections. Pronotum often darker than elytra; legs lighter brown,

femora and tibiae at their bases and apices with dark rings, varying in intensity

and extent. Colour of under side identical with that of upper side, either

extending uniformly over entire surface, or darker in some parts than in others.

Head somewhat exserted, with apex convex and frons slightly depressed ;

upper surface very roughly sculptured, the interantennal and _ interocular

spaces closely covered with deep punctures, which, coalescing on the apical area,

form channels alternating with ridges. Eyes convex and entire. Antennae

extending to about middle of elytra ; first segment long and thickened, second

CHRYSOMELIDAE. 183

very small and also thickened, third slender, about twice as long as second,

fourth slender, longest, twice as long as third ; fifth to eleventh segments about

equal to each other in length. Prothorax broader than long, somewhat narrowed

in front, lateral margins almost straight or very slightly rounded, posterior

margin with a feeble median lobe ; upper surface uneven, with shallow depres-

sions and elevations, gently sloping on each side in front, very roughly

sculptured, covered with coarse and

large punctures, which, coalescing,

form channels and ridges. Scutellain

subpentagonal, longer than broad,

broader at base, narrowing at apex,

which is rounded ; surface strongly

punctate. Hlytra very _ slightly

broader at base than prothorax,

confusedly, closely and_ strongly

punctate ; surface uneven, humerus

strongly elevated, with area posterior

to it depressed; on inner side of

it there is also a depression con-

taining aridge. Around and behind

scutellum a certain area is depressed.

A well-marked depression in middle

of each elytron behind basal area ;

among ridges produced by these de-

pressions on the surface, especially

prominent are a costa parallel to

suture, and a rather large elevation

in middle area. (These depressions

and prominences are best seen when

the insect is held at various angles.) Under side not so hairy as upper side :

abdominal sternites punctate. First segment of posterior tarsi longer than

corresponding segment of anterior or middle tarsi.

Length, 5-6 mm.

Tutuila: Eastern end of island, 1,070 ft., 21.v.1918, 1 example (Kellers).

Avau, 19.11.1926, 1 example. Amouli, 17.11.1926, 1 example (Judd). Fagasa,

9.ix.1923, 4 examples (Swezey and Wilder). Pago Pago, 12-16.iv.1924,

Trxt-FIe. 3.—Stygnobia aenescens, sp.n. X11.

184 INSECTS OF SAMOA.

3 examples (Bryan); 24, 25, 30.i1x.1923, 10 examples (Swezey and Wilder)

(Type, 25.i1x.1928).

Type in the Bishop Museum ; paratype in the British Museum.

Described from twenty examples. It seems evident that the species is

confined to Tutuila.

4. Stygnobia cauta Weise (Text-fig. 4).

Stygnobia cauta Weise, Archiv fiir Naturgesch., \xxxviii, Abt. A., Heft. 10, pp. 154, 1922.

Stygnobia annulipes Weise, loc. cit.

Body oblong-ovate. General colour varying from shining dark red-brown

to lighter brown ; central area of front

of head with a blackish patch, which is

sometimes obsolescent; antennal seg-

ments in most cases tinged with fuscous ;

pronotum may be darker (almost pitch-

black) than elytra; on under side

abdominal sternites may be lighter than

rest of surface, distribution of lighter

and darker shades varying considerably ;

legs often lighter brown; in many cases

at constriction near apex of femora and

at two places on tibiae there are dark

brown rings encircling the limbs; these

rings may be faint or disappear alto-

gether, and may not be seen on all the

legs at once, being well-marked on some

while obsolescent or absent on others.

In some examples before me there is a

black broad longitudinal stripe along the

elytra ; this stripe is also very variable,

appearing as a strongly developed mark

in some examples but becoming very

faint in others; on the basal area the

stripe is bifurcate; when strongly de-

veloped it is broad, covering a considerable portion of the elytral surface.

In some examples the elytral punctures are black,

Text-Fic. 4.—Stygnobia cauta Weise. x 12.

CHRYSOMELIDAE. 185

Head with vertex not very convex, and with a depression on central area ;

completely punctate, punctures on vertex smaller than those on interocular and

interantennal areas, where they coalesce to form a certain rugosity. Area

bounded by roots of antennae, central depression and labrum, more or less

delimited. Antennae reaching about middle of elytra, first segment thick, club-

shaped, long, but shorter than fourth, second very small, third about twice as

long as second, fourth about twice as long as third, fifth somewhat shorter than

fourth, sixth to eleventh segments about equal to each other. Prothorax much

broader than long, sides almost straight, slightly converging towards front,

sharing general contour of prothorax ; upper surface convex in centre, sloping

to sides and more so to front, fairly closely punctate, punctures being round and

having no tendency at all to become elongate or to coalesce with one another ;

posterior lateral angles right angles ; each corner furnished with a fine long seta.

Scutellum almost as broad as long, subpentagonal, with apex rounded, surface

closely punctate. Hlytra shghtly broader at base than prothorax, sides almost

parallel, somewhat narrowing towards apex ; surface closely punctate. On the

basal area on the inner side of the humerus there is a depression, on the inner

side of which is another depression; these depressions are black, in many

examples, owing to a continuation of the black elytral stripe referred to in the

short diagnosis above.

Length, 4-63 mm. Type example, 65 mm. Cotype, 54 mm.

Type and cotype of S. cauta Wse. in the Deutsches Kntomologisches

Museum.

Type of S. annulipes Wse. in the same Museum.

Upolu: Aleipata, iv.1924, 5 examples; v.1924, 1 example. Lalomanu,

x1.1924, 1 example. Apia, 4 and 10.11.1924, 2 examples (Armstrong) ; 11.1924,

9 examples ; iv. 1924 and 1925, 2 examples; v.1924, 3 examples, and v.1925,

3 examples; x.1924, 1 example; xi1.1924, 3 examples; 11.1925, 1 example.

Malololelei, 2,000 ft., 11.1924, 1 example; iv.1924, 2 examples; vi.1924, 4

examples. Leulumoega, 14.1x.1923, 9 examples (Swezey and Wilder). Muli-

fanua, 16.vu.1925, 1 example (Wilder).

Manua: Tau, 27.ix.1923, 1 example (Swezey and Wilder).

Sava: Fagamalo, xi.1925, 6 examples.

Tutuila: 1,100-1,200 ft., iv.1918, 1 example (Kellers). Pago Pago,

20.1x.1923, 2 examples (Swezey and Wilder); 16.iv.1924, 2 examples (Bryan).

Leone Rd., 7.1x.1923, 2 examples (Swezey and Wilder).

186 INSECTS OF SAMOA.

There are sixty-two specimens of this species in the present collection, and,

together with the four, including the types, sent by Dr. Walther Horn, I have

examined sixty-six examples.

In view of the small amount of variation shown by so much material, |

cannot help coming to the conclusion that S. annulipes Wse. should be con-

sidered as a variety of S. cauta Wse. ; thus the former name becomes a synonym

of the latter.

Variation.—The variation in size is considerable. It will be noticed that

there is a difference of 1 mm. in length between Weise’s type and cotype, and

there are examples before me which are as small as 4 mm. There is a corre-

sponding apparent variation in shape in which the body is slightly narrowed

towards the apex. If a single small example is captured and compared with

the type there will be considerable doubt as to whether it belongs to the same

species.

The variation in colour and markings have already been indicated in

the short colour diagnosis above. There is more structural variation in the

sculpturing of the head than elsewhere. The confluence of punctures in the

interantennal area, producing a rugosity, is variable.

5. Stygnobia variabilis, sp. nov. (Text-fig. 5).

Body ovate. General colour shining dark brown ; in uniformly dark brown

examples, pronotum and thoracic sterna often darker than rest of body. The

colour varieties are as follows: vertex of head may have a longitudinal stripe,

broad at base, narrowmg towards mouth-parts. Elytra in many examples

with a broad stripe along suture, covering a considerable area on each side, and

about middle sending off an arm on each side, which encircles a convex area at

base (in some examples this encircling process is incomplete) ; on apical area

sutural stripe broadening considerably, covering in an ill-defined manner a large

area on each elytron. In some examples the sutural stripe ends abruptly about

the middle, but the black colour on the apical area is nevertheless present, and

continuing forwards forms a longitudinal stripe. In the specimens with the

elytral markings the pronotum may be completely black, or may have certain

areas at the sides brown and the rest black, while the lateral edges of the elytra

are often black. Among the patterned specimens, the tibiae diffusedly and

the hind femora at the point of articulation are often black. Some examples

CHRYSOMELIDAE. 187

are completely black, except that the mouth-parts, antennae and tarsi remain

brownish fuscous.

Head with vertex convex ; front divided by a transverse impressed line or

constriction above roots of antennae; surface strongly and closely punctate,

punctures in some cases being confluent with one another and producing ridges ;

edge along upper border of eyes deeply impressed. Eyes strongly convex.

Antennae extending slightly beyond

middle of elytra; first segment long

and club-shaped, second small, thick-

ened, third slender, about twice as

long as second, fourth always longer

than third, although relative lengths of

third and fourth segments vary to a

certain extent; fiith and following

segments about equal, apical segments

apparently very slightly thickened.

Prothorax broader than long, some-

what narrowed in front, posterior

lateral angles acute, each of the four

corners with a fine seta, upper surface

convex in centre and sloping on each

side, more so in front; sculpturing

varying considerably ; entire surface

closely covered with punctures, which

are somewhat elongate and in many

specimens coalesce, producing oblique J

longitudinal ridges; this ridged con- ft R

dition may be very pronounced, OF Tpyy-mre. 5.—Stygnobia variabilis, sp. n. X 18.

may be altogether wanting ; between

these two limits various gradations may be seen. (The variation in the surface

structure of the prothorax renders the identification of a single example, in the

absence of a series, very difficult.) Scutellum almost pentagonal, fairly broad

though longer than broad, apex rounded; surface closely punctate. Llytra

as broad at base as prothorax, with a fairly large area at base gently convex

(better seen when insect is held at certain angles); entire surface closely and

confusedly punctate. Under side as in generic diagnosis.

188 INSECTS OF SAMOA. .

Length, 3-33 mm.

Upolu: Malololelei, 2,000 ft., 24.11.1924, 11 examples; 12.11.1924, 13

examples (including the type); 1v.1924, 1 example; 25.iv.1924, 3 examples ;

18.1v.1925, 15 examples ; vi.1924, 23 examples; 14-30.vi.1924, 11 examples ;

5.1.1924, 1 example ; 20.vi.1924, 1 example ; 2.vii.1924, 1 example (Armstrong) ;

vul.1925, 4 examples (Wilder) ; 23.x1.1924,19 examples ; 28.xi.1924, 1 example.

Aleipata, iv. 1924, 1 example. Leulumoega, 14.i1x.1923, 2 examples (Swezey

and Wilder). Vailima, 600 f{t., 2.1.1925, 1 example; 18.x.1924, 3 examples.

Apia, 11.1924, 1 example ; v.1924, 4 examples; Mt. Vaea, 1,500 ft., 20.x11.1924,

1 example ; 13.1x.1923, 1 example ; 15.1x.1923, 2 examples (Swezey and Wilder).

Total: 120 examples from Upolu.

Tutuila : 760-900 f{t., 1v.1918, 31 examples ; 21.v1.1918, eastern end of

island, 1,070 ft., 2 examples; 30.vi.1918, centre of island, 900-1,000 ft., 3

examples ; 21.vui.1918, 1,000 ft., 10 examples ; 25.vi1.1918, 1,000 ft., 5 examples ;

xu.1918, 1,200 ft., 1 example (all examples under the various dates were collected

by H. C. Kellers). Pago Pago, 2.x11.1924, 4 examples ; 14.xu.1924, 2 examples ;

9.1x.1923, 1 example ; 10.ix.1923, 5 examples ; 30.1x.1923, 5 examples (Swezey

and Wilder); 12.vi.1924, 1 example; 16.iv.1924, 2 examples; 18.iv.1924,

1 example (Bryan). Fagasa, 9.1x.1923, 4 examples (Swezey and Wilder) ; one

of the labels bears the words ‘“ nutmeg tree.” Total: 77 examples from

Tutuila.

Savan: Fagamalo, xi.1925, 1 example. Salailua, 20.v.1924, 1 example ;

23.v.1924, 5 examples (Bryan). Safune, rain forest, 2,000-4,000 ft., 8.v.1924,

3 examples ; lower forest, 1,000-—2,000 ft., 5.v.1924, 1 example (Bryan). Total :

11 examples from Savaii.

In describing this species I have examined two hundred and eight examples,

from two of which three balsam mounts have been made.

Type in the British Museum ; paratypes in the Bishop Museum.

6. Stygnobia minuta, sp. nov. (Text-fig. 6).

Body oblong-ovate. General colour dark brown, legs lighter brown ;

pronotum in some cases black, and elytra with a broad black stripe covering

almost entire surface except margins and suture. (In some examples the black

colour of the pronotum and elytra has almost disappeared.) Antennal segments

blackish, except basal three, which are lighter brown.

CCHRYSOMELIDAE, 189

Head with vertex convex, uniformly and strongly punctate without any

marked depression or impressed lines. Antennae extending to apical area of

elytra ; first segment long and

club-shaped; second thick, \

about one-half as long as

first ; third slender and longer

than second; fourth longer

than third ; following segments

about equal to each other in

length, and slightly and gradu-

ally increasing in thickness.

Prothorax broader than long,

narrowed in front ; posterior

angles rounded, not acute ;

upper surface convex in centre,

slopmg down at sides and

more so in front, strongly and

closely punctate, punctures

coalescing. Llytra as broad

at base as prothorax ; sides

parallel to a certain extent,

which gives the insect a broad,

squarish appearance as com-

pared to S. varabilis; a

certain area at the base on the

inner side of the humerus

slightly convex; confusedly

and strongly punctate, the

punctures closer together and larger than those of S. varrabils. Under side as

in the generic diagnosis.

Length, from a little over 2 mm. to 2 mm.

Upolu: Malololelei, 2,000 ft., iv.1924, 7 examples ; 22.xi.1924, 2 examples,

one of which is the type.

Tutuila : Pago Pago, 16.iv.1924, 1 example (Bryan).

Type in the British Museum ; paratype in the Bishop Museum.

Described from ten examples.

TEXT-FIG. 6.—Stygnobia minuta, sp. n. X 26.

190 INSECTS OF SAMOA.

7. Rhyparida subaeneicollis Fairmaire.

Rhyparida subaenercollis Fairm. Le Naturaliste, i, p. 76, 1879 ; Ann. Soc. Ent. Fr. (6), 1, p. 484, 1881.

This species is not represented in the collections under study. It is

apparently confined to Samoa, and has not been reported from any other locality.

8. Stethotes rufonigra, sp. nov. (Text-fig. 7).

Body ovate, much narrowed posteriorly. General colour black, with an

ill-defined area on apical half of elytra red; antennae piceous, three proximal

segments yellow-brown; palpi

similarly coloured.

Head: vertex convex with a

median channel, on each side of

which are fine oblique ridges pro-

ducing a strigose appearance. In-

terocular space somewhat depressed

and with a few punctures. Hyes

convex; between each eye and

convexity of vertex of head a deep

sulcus. Antennae extending a little

beyond middle of elytra, first seg-

ment thickened and club-shaped,

second shorter and thinner than

first but thicker than third, fourth

\ longer than third, fifth equal to

i fourth, sixth somewhat shorter than

| fifth, seventh, and following seg-

8 ments somewhat thicker, seventh

segment slightly longer than eighth,

eighth, ninth, and tenth segments

equal, eleventh segment ovate, blunt

at apex. Prothorax narrowed in

front and convex, its sides sloping

and margined; basal margin with

a deep channel; upper surface completely covered with round punctures ;

posterior lateral angles each with a fine seta. Under a high power the

TERI

TExt-FIe. 7.—AStetholes rufonigra, sp. n. X 22.

CHRYSOMELIDAE. 191

background is seen to be finely shagreened. Scutellum triangular, with

rounded apex, slightly convex, finely shagreened. Hlytra regularly punctate-

striate, much broader at base than prothorax; at base on inner side of

humerus is a convex area; on each elytron are thirteen rows of punctures,

including a scutellar and an extreme marginal row; counting from suture,

ninth and tenth rows arise from behind, and twelfth row arises from below

humerus, all being very short ; rows meeting in pairs on narrowed apical area.

Under side: legs of usual length in this genus; femora thickened in middle

and without any spine; middle and hind tibiae emarginate on outer side at

apex ; claws strong, bifid.

Length, 3 mm.

Savati: Safune, rain forest, 2,000—4,000 ft., 3.v.1924 (Bryan).

Type in the Bishop Museum.

Described from one example.

The study of the Kumolpinae of the present collection lends support to an

idea which suggested itself to me when I was studying other island faunas, such

as that of the Seychelles. In that case also I was confronted with the same

difficulty of judging the limits of a species which showed structural variations.

The idea may be formulated thus: in island faunas species tend to become more

plastic than in continental faunas. I put forward this principle tentatively,

and its validity or otherwise will be proved as more experience is accumulated.

Mr. K. G. Blair tells me that he observed the same phenomenon in a Lycid

beetle, Samoaneros acuticollis Fairmaire (Part 4, p. 101 above). Dr. G. A. K.

Marshall also tells me that amongst the Samoan Curculionidae the same

feature is noticeable in some species. It would be premature to speculate here

as to the causes of such variation in island faunas.

CHRYSOMELINAE.

9. Plagiodera samoana, sp. nov. (Text-fig. 8).

Body ovate, strongly convex, highest point of convexity being middle of

elytra ; seen in profile, from this point upper surface slopes down more abruptly

in front than behind. General colour shining dark brown ; in some cases under

side is tinged with blackish, in others it is pitch-black ; head and pronotum always

brown ; elytra pitch-black. Among nine examples before me, in one the pitchy

colour is lighter and in two it has become brown, except the apical area of the

Iv. 3 2

192 INSECTS OF SAMOA.

elytra. The scutellum always shares the colour of the basal area of the elytra.

The four basal segments of antennae are brown, the rest black. The legs are

always lighter brown.

Head broad, its width sufficient to allow it to fit into emargination of front

edge of pronotum; upper surface deeply marked with a A-shaped impression,

and also bearing very fine and irregularly placed punctures, some of which are

somewhat elongate. Eyes strongly convex. Antennae extending slightly

beyond humerus, their roots separated by whole width of frons; first segment

largest, thick, club-shaped, second small, also somewhat club-shaped, third

longer than second, fourth shorter

than third; fifth and following

segments thickened, more opaque

than basal segments, about equal,

although fifth appears to be some-

what smaller and last segment is

bluntly pointed. Prothorax more

than twice as broad as long, its front

margin widely emarginate, narrower

than posterior margin, sides oblique,

very gently rounded, anterior and

posterior lateral angles being

rounded right angles; upper sur-

face smooth, very sparsely and

extremely minutely punctate,

punctures only visible under a

Text-Fic. 8.—Plagiodera samoana, sp. n. X 9. high power. Scutellum large, trian-

gular, with apex rounded and _ sur-

face smooth, impunctate. Hlytra strongly convex, narrower at base, broadening

behind, again narrowed towards apex; humerus sharply raised; surface

smooth, very sparsely and extremely minutely punctate, punctures only visible

under a high power. Under side smooth, shining, hardly punctate. Legs stout ;

claw segment of tarsi projecting much beyond bilobed segment, which is split

along middle ; claws simple.

Length, 64 mm. ; breadth, 5} mm.

Upolu: Malololelei, 2,000 ft., 18.iv.1925, 6 examples (including the type) ;

28.x1.1924, 2 examples.

CHRYSOMELIDAE. 193

Tutuila : 1,100-1,200 ft., iv.1918, 1 example (Kellers) ; in this example the

brown has an admixture of red in it, and the elytral punctures are somewhat

bolder.

Type in the British Museum.

Described from nine examples.

GALERUCINAE.

Aulacophora Chevrolat.

Aulacophora Chevrolat in d’Orbigny, Dict. Univ. Hist. Nat., ii, p. 337, 1842.

Orthaulaca Weise, Deutsch. Ent. Zeitschr., Jahrg., 1892, p. 393, 1892.

The genotype of Aulacophora Chevrolat is Galeruca quadraria Olivier.

In 1892, Weise (loc. cit., p. 392) suggested that the name Aulacophora should

lapse on the ground that it is preoccupied by a genus of plants ; this contention,

however, is not in accordance with the rules of zoological nomenclature. Had

the suggestion remained buried in the pages of the Deutsch. Ent. Zeitschr. it would

not have mattered much, but its author has given effect to it by altering the

whole arrangement of the species of this large genus in his Catalogue of the

Galerucinae in Junk and Schenkling’s Coleopterorwm Catalogus (Berlin, 1924),

thus necessitating a further rearrangement, which I shall attempt in a future

publication. For the purposes of the present paper I include the three following

species in Aulacophora, thus giving it recognition as a genus which cannot be

abolished.

10. Aulacophora similis Olivier.

There are three secondary sexual characters by which the males of this

species can be recognised, namely :

(1) The first segment of the antennae is very greatly enlarged, more so than

the same segment in the females.

(2) A certain area behind the humerus is covered with erect hairs.

(3) The apical segments of the abdomen are modified ; on the ventral side

the last visible sclerite is trilobed, the middle lobe having on each side a deep

incision, which has a fold at its base.

Upolu: Apia, 19.11.1923, 1 9 (Armstrong); v.1924, 2 gg, 1 2; ix.1924,

9 99, 4 §g, 1 g§ dissected and mounted in balsam; 15.x.1924, 1 g; xu.1924,

194 INSECTS OF SAMOA.

13,299: v.1925,19. Aleipata, 10.iv.1924,1 9; iv.v.1924,499. Lalomanu,

x1.1924, 2 99.

Tutuila: 1,000-1,200 ft., 2 $g, 2 99 (Kellers). Amauli, 5.ix.1923, 1 9

(Swezey and Wilder). Afono Trail, 25.ix.1923, 1 9, 1 ¢ (Swezey and Wilder).

Leone Road, 7.1x.1923, 1 9, 1 3; 18.ix.1923, 1 § (Swezey and Wilder) ; 19.11.1924,

1 3g, 1 @ (Bryan); 12.vili.1925, 1 9. Pago Pago, 18.iv.1924, 1 2 (Bryan) ;

20.1x.1923, 1 9; 22.ix.1923, 5 99, 2 3, all caught on pumpkin (Swezey and

Wilder).

Savail: Lower forest, 1,000-2,000 ft., Safune, 5-8.v.1924, 2 99, 2 3d;

4.v.1924,1 S$; 12.v.1924, 2 oo.

Nuutele: xi.1924, 1 9.

Tau, Manua: 27.1x.1923, 2 $g (Swezey and Wilder).

Tonga Islands: Vavau, Neiafu, 9.ii1.1925, 1 ¢; 1.1i1.1925,1 g. Nukualofa,

14.11.1925, 1 J; 24.11.1925,1 9. Total: sixty-five examples.

In the collection of the British Museum there is a very large series of this

species showing a wide distribution, from the Malay Archipelago to China and

Japan in one direction, and to Australia in the other.

11. Aulacophora quadrimaculata Fabricius.

Crioceris quadrimaculata Fabricius, Sp. Ins., i, p. 152, 1781.

Fabricius described this species in the work cited above from two speci-

mens in the Banksian Collection, which is preserved in the British Museum

(Natural History). The specimens in question are stated by Fabricius to have

been obtained by Dr. Forster at the Cape of Good Hope, which is probably incor-

rect ; but the statement at least shows that the insects were collected in a

distant foreign land, and notin Europe. In Ent. Syst., i (2), p. 12, 1792, Fabricius

bestowed the name Crioceris quadrimaculata upon a second species, stated to

have been found in Southern Germany. This latter species, the type of which

is in the Lund Collection, in all probability is in no way telated to the Crioceris

quadrimaculata in the Banks Collection. At any rate, whatever may be the

insect in the Lund Collection, the name given to it is not valid and need not

concern us here.

Among those beetles occurring in Oceania and the adjacent regions with

the type of pattern consisting of two large black patches on each elytron, one

of the means by which species may be differentiated is aflorded by a secondary

CHRYSOMELIDAE. 195

sexual character of the male. In some species in the male the basal segments

of the antennae are dilated, while in others this dilatation is absent. The

particular nature of the dilatation has also been pressed into service to separate

Species among those that have males with dilated basal segments. It may be

remarked that species in which the basal segments are not dilated in the male

nevertheless have these segments somewhat thicker in the male than in the

female. The black patches on the elytra, on the head and on the under side of

the body are variable within a species, and transitional forms exist, but these

markings have been used in separating species.

It is quite probable that Galleruca austrocaledonica Montrouzier, Ann. Soc.

Ent. Fr. (4), 1, p. 299, 1861, and Aulacophora tetrastictoptera Lea, Mem. Queens-

land Mus., viii, 1, pp. 50-1, 1924 (cotypes in the British Museum) are identical

with A. (Crioceris) quadrimaculata F.; but the question can never be definitely

settled because the Fabrician type in the Banks Cabinet is a female, and it is

impossible to ascertain whether the males of the Fabrician species have the basal

segments of the antennae dilated or not. Moreover, the female of the Fabrician

species agrees closely with the females of several other species, whether the males

of the latter have dilated segments in their antennae or not. The difficulties

that have arisen here cannot be settled by the comparison of structural characters.

In these circumstances I propose to call the Samoan species by the oldest

name given to this type of insect occurring in the regions under study, and

I suggest that experimental breeding be undertaken by those who have the

opportunity, in order to ascertain whether we are dealing with a single species

with dimorphic males.

Variation in the Samoan Specimens.

1. The males are somewhat smaller, and have the basal segments of the

antennae simple, ?.e. not dilated.

2. The postocular black patches vary in size; in one or two cases they

have become larger, and have coalesced in the interocular space.

3. The elytral patches also vary in size; their boundaries are sometimes

well defined, sometimes irregular. Among the examples from Savaii, the

posterior elytral patch is enlarged and sends off extensions to meet the anterior

patch. It is possible to conceive a case in which the whole elytral surface

might become black owing to the enlargement and confluence of the four elytral

spots.

196 INSECTS OF SAMOA.

Geographical Distribution.

Aulacophora tetrastictoptera Lea (considered as synonymous with the

Fabrician species) has been taken in the following localities :—Australia :

Northern Territory (Blackburn’s Collection), Darwin (W. K. Hunt), Roper

River (N. B. Tindale); Queensland, Cairns district (Blackburn’s Collection).

New Guinea: St. Joseph’s River (Sir Wm. MacGregor).

Aulacophora austrocaledonica Montrouzier (also considered as synonymous

with the Fabrician species) was collected in New Caledonia.

In the collection of the British Museum other examples resembling the

Fabrician species are labelled as follows: Fiji Islands, Ovalau ; Nova Holland

(De Boulay) ; N. Australia, Cape York Pen., Cowal Creek, 15.vii.1924 (G. H.

Wilkins) ; N. T. Australia, Groote Eylandt, 27.11.1925 (G. H. Wilkins).

In the material under discussion the following specimens were found :

Upolu: Aleipata, iv.1924, 1 example. Siumu, 26.xi1.1923, 1 example

(Armstrong). Apia, 29.vili.1924, 1 example.

Manua: Tau, 20.11.1926, 1 example (Judd) ; 27.1x.1923, 1 example (Swezey

and Wilder).

Savaii: Fagamalo, xi.1925, 1 example. Salailua, 19.v.1924, 3 examples

(Bryan).

Tutuila: Pago Pago, 14.xii.1925, 2 examples; 18.iv.1924, 1 example

(Bryan) ; 9.ix.1923, 5 examples ; 10.ix.1923, 1 example ; 18.ix.1923, 1 example ;

30.1x.1923, 1 example (all these collected by Swezey and Wilder); 3,000 ft.

iv.1918, 1 example (Kellers). Fagasa, 9.ix.1923, 1 example. Amouli, 5.1x.1923,

1 example (Swezey and Wilder). Leone Road, 19.ii.1924, 1 example (Bryan).

Total: twenty-four examples.

12. Aulacophora nigrobrunnea, sp. nov. (Text-fig. 9).

Body oblong, somewhat broadened behind. Elytra black; antennae,

prothorax, scutellum and under side brown, sometimes darker or piceous.

Head somewhat exerted; vertex sometimes with a few punctures and

always finely reticulate ; interocular space with a deep transverse impression,

crossed by a deep median longitudinal impression ; interantennal space with a

ridge, continued to the labrum; eyes strongly convex; antennae hairy, long,

slender, extending slightly beyond middle of elytra, first segment long and

CHRYSOMELIDAE. 197

club-shaped, second small, about one-third as long as first, third, fourth, and

fifth segments about equal, in some specimens third segment, in others fourth

appearing to be somewhat longer; sixth and following segments somewhat

shorter and about equal to each other. Prothorax rectangular, broader than

long, each corner with a fine seta; at anterior angles sides somewhat incurved ;

lateral margins slightly re-

flexed; upper surface sparsely

and finely punctate; post-

median transverse depression

varying in depth and some-

times interrupted in the middle.

Scutellum triangular with

rounded apex; surface some-

what convex and very finely

shagreened. Jlytra broader at

base than prothorax ; humerus

prominent ; entire surface finely

shagreened and also fairly

strongly punctate, not smooth,

but with ill-defined longitudinal

ribs. Under side covered with

fine hairs ; tibiae with a sharp

spine at apex ; claws bifid.

Length, 74 mm.; breadth,

34 mm.

Upolu: Malololelei, 2,000

ft., 25.11.1924, 1 example; 14-

30.v1.1924, 2 examples (includ- y

ing the type). Vailima, 16.v. 4

1924, 1 example. ?

Tutuila : 1,200 ft., xii.1918, Text-Fic. 9—Aulacophora nigrobrunnea, sp. n. x 10.

1 example (Kellers). Centre of

island, 900-1,200 ft., 30.vi.1918, 1 example (Kellers). Leone Road, 19.11.1924,

1 example (Bryan). Pago Pago, 10.ix.1923, 1 example (Swezey and Wilder).

Savaii: Safune, rain forest, 2,000-4,000 ft., 23.v.1924, 2 examples

(Bryan).

iso

198 INSECTS OF SAMOA.

Another example before me has ‘“‘ Samoa” on the locality label, and also

bears a label with the word “‘ Orthaulaca ”’ on it in Weise’s handwriting.

Type in the British Museum.

Described from eleven examples.

The coarser punctuation and general rough sculpturing of the elytra dis-

tinguish this species from all other similarly coloured ones known to me.

Plesistia, gen. nov.

Body subcylindrical, oblong, with rounded apex; subopaque, head and

pronotum apparently somewhat more shining. Antennae extending to about

middle of elytra, first and fourth segments long. Prothorax a little more than

twice as broad as long, with rounded sides; the anterior and posterior lateral

angles are rounded right angles, each bearing a fine seta ; upper surface uneven

with smooth shallow depressions, very sparsely punctate. Scutellum pubescent.

Elytra parallel-sided, and each with ten ribs including a short scutellar one,

suture raised ; each alternate rib more strongly raised than the others, so that

there are four strong and five weak ribs on each elytron ; scutellar rib weak ;

intervals between ribs irregularly punctate. Under side hairy; anterior

coxal cavities completely closed behind (see Text-fig. 10); legs strong, upper

surface of tibia with a fine rib, under side rounded, and apex without a spine.

Claws strong, with an angulate projection at base on under side (see Text-fig. 11a).

Genotype: Plesistia brunnea Maulik.

Range: Samoa.

Relationship —The new genus described above is related to Pleronexis Weise

(Nova Guinea, v, Zool., p. 321, 1908) in that both possess ribs on the elytra and

hairs on the scutellum. In Plesistia the anterior coxal cavities are closed behind

(see Text-fig. 10), while according to Weise they are open in Pleronexis. Through

the courtesy of Dr. J. B. Corporaal, however, I have had the opportunity of

examining Weise’s type, and I find that the anterior coxal cavities are not open

behind. The closure of the coxal cavities in Pleronemis is of the same type as in

Plesistia. The difference between the two genera lies in the fact that in Pleronexis

all the ribs on the elytra are equally raised, while in Plesistia a strongly raised

rib alternates with a less elevated one. As regards geographical distribution

the two genera are alike.

CHRYSOMELIDAE. 199

13. Plesistia brunnea, sp. nov. (Text-figs. 10 and 11).

General colour grey-brown; in some specimens brown colour more

prominent, grey colour being more conspicuous on pronotum and head ; elytra

sometimes speckled with red spots; vertex of head black, generally concealed

by pronotum. Eight apical segments of antennae blackish on upper, brownish

on under side, first three segments and basal part of fourth brown. On under

side, portions of metathorax and the abdominal sternites blackish, tarsi and apices

of tibiae piceous.

Head large, somewhat exserted, impunctate, vertex with median longi-

tudinal impressed line which is continued along interantennal space to base of

labrum; base of antennae situate in an excavated area. First segment of

antennae long and club-shaped, second much shorter than third, latter shorter

than either first or fourth, which is the longest ; fifth and following segments

Text-Fic. 10.—Coxal cavities of Plesistia brunnea.

about equal and more hairy, last segment bluntly pointed. Prothorax with

upper surface having a somewhat flattened appearance, with a shallow depres-

sion anteriorly on each side of middle longitudinal line. (The general uneven-

ness of the surface can be more easily detected if the insect is examined from

different angles.) Scutellum triangular, with broadly rounded apex and hairy

surface. lytra slightly broader at base than prothorax; each elytron with

ten ribs including a short scutellar one, but excluding suture, which is also raised

like a rib; short scutellar rib anastomosing with suture ; rib next suture weak,

alternate ribs more strongly raised ; between lateral margin and next strong

rib is a wide space, which contains last weak rib and is closely and irregularly

punctate ; lateral margin very slightly explanate.

Length, 8 mm.

Upolu: Apia, v.1924, 1 example ; v.1925, 1 example ; 25.v.1924, 1 example ;

vil.1924, 4 examples (including the type); ii.1924, 1 example; 1.1924,

200 INSECTS OF SAMOA.

1 example; 11.v.1924, 1 example. Malololelei, 18.1v.1924, 1 example (Arm-

strong). Mulifanua, 9.x1.1925, 2 examples; 12.1x.1923, 1 example (Swezey

and Wilder). Tafua volcano, 1917, 1 example (Swale); 27.v.1924, 1 example

(Bryan).

Tutuila: 18.xii.1918, 3 examples; 1,100-1,200 ft., 18.iv.1918, 1 example

Text-Fic. 11.—Plesistia brunnea, sp.n. X 9: a, claw.

(Kellers) ; eastern end of island, 1,070 ft., 21.vi.1918, 8 examples (Kellers).

Pago Pago, 3,000 ft., 18.1v.1918, 4 examples. Amouli, 17.i11.1926, 1 example

(Judd).

In the British Museum Collection there are two examples taken by Dr. H.

Swale at Apia, 6.1x.1916, one of which is not a perfect specimen, while the other

is smaller (7 mm.) and yellow in colour. In all probability these individuals

CHRYSOMELIDAE. 201

belong to the present species, but in default of further material the question

cannot be definitely settled.

This species also occurs at Cuvu, Fiji Islands, whence there are three

examples in the British Museum (10.x.1919, W. Greenwood).

Type in the British Museum ; paratypes in the Bishop Museum.

Described from thirty-eight examples.

HALTICINAE.

Nesohaltica, gen. nov.

Body oblong with apex of elytra rounded. Head broad, vertex delimited

from interocular space by a deeply impressed transverse line; raised areas in

interocular space not strongly developed. Antennae eleven-segmented, with

two basal and five apical segments thickened. Eyes convex, but not very

strongly so and nowhere emarginate. Prothorax broader than long, with

rounded sides, each corner with a pore bearing a fine seta ; anterior pores situated

somewhat behind anterior angles so that latter appear truncate. Hlytra con-

fusedly punctate. Under side: anterior coxal cavities open behind ; intercoxal

process of prosternum broad, concave, with its surface rough. Hind femur

strongly dilated ; hind tibia with upper surface flat, not sulcate, and with short

spine near apex beneath tarsus ; latter not more than half as long as tibia, first

segment not longer than following segments together. Claws divaricate.

Genotype : Nesohaltica nigra Maulik.

Range: Samoa.

14. Nesohaltica nigra, sp. nov. (Text-fig. 12).

General colour black tinged with blue, in some examples the black much

diluted by pitch-brown ; tibiae and tarsi more pitch-brown ; five basal seg-

ments of antennae yellow-brown, remainder blackish or pitchy.

Head with vertex impunctate ; in interocular space near inner margin of

each eye a round depressed spot; a longitudinally impressed line dividing the

_ moderately raised frontal areas. Antennae extending a little beyond middle

of elytra ; first segment long and club-shaped ; second shorter, also club-shaped,

about equal to third in length; third, fourth and fifth segments more slender,

about equal to each other in length; sixth and seventh slightly thicker, equal

202 INSECTS OF SAMOA.

to each other; eighth, ninth and tenth segments thick, somewhat shorter ;

eleventh segment same thickness, longer and bluntly pointed. Prothorax with

sides margined and rounded ; upper

surface uniformly convex and con-

fusedly punctate, some of the punc-

tures finer than others. Scutellum

small, broader than long, triangular

with apex broadly rounded, surface

impunctate, finely shagreened. Hlytra

broader at base than prothorax,

confusedly and strongly punctate ;

humerus raised, convex. Under side

shining, with sparse, fine, whitish

hairs; abdominal sternites finely and

transversely striated. Other struc-

tures as described in generic diagnosis.

Length, 24 mm.

Upolu: Mt. Vaea, 1,500 {ft.,

20.x11.1924, 1 example (type).

Vailima, 24.v1.1924, 2 examples.

Malololelei, 2,000 ft., vi.1924, 2

examples. Tuaefu, 16.1x.1923, 3

examples (Swezey and Wilder).

Trext-Fric. 12.—Nesohaltica nigra, sp. n. x 380. Tutuila: Pago Pago, 9.1x.1923,

1 example (Swezey and Wilder).

Savail: Salailua, 21, 22.v.1924, 7 examples (Bryan).

Type in the British Museum.

Described from sixteen examples.

15. Sphaerophyma insularum, sp. nov. (Text-fig. 13).

Body ovate, strongly convex. General colour shining black; antennae

and tarsi of all legs light brown; parts of abdominal sternites darker brown,

especially those that generally remain covered by the large posterior femora ;

portions of tibiae dark red-brown (especially when seen by transmitted light).

Head in repose deeply retracted within prothorax ; interocular space slightly

convex, more so above roots of antennae, and with two round punctures, one on

CHRYSOMELIDAE. 203

each side close to eye-margin and each bearing a fine seta; clypeus sharply

triangular, somewhat raised, with a sharp median longitudinal ridge, and a few

long scattered setae. Eyes large, occupying a large portion of the head, though

not so closely approximate as in the genus Paradibolia. Antennae eleven-

segmented, extending a little beyond humerus, slightly thickened towards apex,

three basal segments almost without hairs, remainder more hairy ; first segment

longest and club-shaped, second small and ovate, third slender somewhat longer

than second ; fourth and following segments thickened ; fourth and fifth seg-

ments equal, each somewhat longer than any of the remaining segments, which

are about equal to one another, terminal segment bluntly pointed. Prothoraa

transverse, longest in centre ; basal margin

bisinuate on each side, and lobed in middle ;

sides margined and oblique ; upper surface

convex, sloping on each side, very minutely

and confusedly punctate, punctures not

close together ; each of the four corners

with a raised pore for reception of a seta.

Scutellum small, triangular, impunctate.

Elytra hardly broader at base than pro-

thorax, very minutely and not very closely

punctate; on a background of confused

punctures ten regular rows, including a

short scutellar row, recognisable on each pyye-mc. 13.—Sphaerophyma insularum,

elytron ; these rows not at regular intervals, Sp) ns 114.

two pairs on lateral area closer to each

other than those on discal area; between last row and elytral lateral margin

a wide space of confused punctures; regularity of the rows not well main-

tained on apical area, where punctures become more obsolescent, while on

basal area rows are more evident. Under side: abdominal sternites minutely

punctate and sparsely covered with whitish hairs; owing to enormous size of

posterior femora, which generally remain pressed against abdomen, sternites

appear somewhat concave. LElytral epipleurae broad, vertical. Anterior coxal

cavities open behind; intercoxal process of prosternum broad, with surface

rough, punctate and margined on each side; in repose, prosternal process

closely opposed to mesasternal process, which is of same width. First abdominal

sternite with a median, longitudinal, well-defined oval area. Posterior femora

204 INSECTS OF SAMOA.

strongly dilated; posterior tibiae short, fitting closely into inner surface of

corresponding femora; tibia (Text-fig. 15k) gradually broadening towards

apex, which is drawn out into a point, its surface being somewhat convex

proximally, and somewhat concave at broadest part; tarsus arising from a

point on concave surface distant from apex; tibial spur greatly enlarged so

as to form a thick club-shaped process, surface of which appears ridged ; lateral

margins of process sinuous, outer margin more so than inner; tarsus almost

as long as tibia ; claws appendiculate.

Length, 3} mm., greatest width, 2} mm.

Tutuila: Pago Pago, 30.1x.1923, 1 example (type) (Swezey and Wilder).

Leone Road, 7.ix.1923, 1 example (Swezey and Wilder).

Type in the British Museum ; paratype in the Bishop Museum.

Described from two examples.

It will be noticed that the form of the hind tibia (cf. 7, &, Text-fig. 15) in the

genotype of Sphaerophyma differs from that in the present species, but the tibial

processes in both cases are similar in form and structure, 7.e. in the possession

of ridges on the surface. In other structures considered collectively S. sularum

resembles the genotype, and I therefore consider the difference in the form of

the hind tibia as specific ; examination of further material may alter this view.

In determining the relationship of this species it was found necessary to

make a comparative study of the structure of the posterior legs of insects

belonging to the genera dealt with below. In these the insects show special

modifications of the hind tibiae, which possess taxonomic value. As a result

of the study the following general statements have been framed and the

characters analytically shown in a table, accompanied by illustrations.

(1) The posterior femur is enormously dilated, and is held pressed against

the abdomen, where a depression has been developed on the ventral surface.

The outer edge of the femur is broadly rounded, and the inner has a slight

concavity for the reception of the corresponding tibia.

(2) The tibia is always short, never exceeding the length of the inner side

of the femur. It is narrow and cylindrical near the point of articulation with

the femur, whence it gradually broadens towards the apex. It isa solid structure,

having an upper and a lower surface, and two lateral margins, that nearer the

body being termed the inner and the other the outer margin. The upper surface

is flat, or somewhat convex, and without hairs, while the lower is semicylindrical,

often with a clothing of hairs, more especially near the tip. The lateral margins

CHRYSOMELIDAE. 205

are generally straight near the base, and sometimes continue so to the end, but

they are often undulate, dentate, serrate or setate. The extreme end of the

tibia is rounded, or produced in various ways.

(3) At the broad-end apex of the tibia the upper surface is concave or some-

times slightly so, and in the concavity is articulated the tarsus, immediately

beneath which is the process or spur.

(4) The tarsus is almost as long as the tibia, or sometimes longer. Of the

four tarsal segments, the first is the longest, and often as long as the remaining

Text-Fic. 14.—Hind tibiae of :—(a) Diboloides bicolor; (b) Dibolosoma quadripustulata ;

segments together; the second is always short; the third is bilobed; the

fourth is long, and, arising from the base of the bilobed segment, projects much

beyond it ; at its apex it bears a pair of claws. A claw may be simple or may

have an angular projection underneath at the base, in which case it is called

appendiculate.

(5) The tibial process or spur varies in length ; it has the shape of a rod or

club, with its apex rounded, emarginate, split or pointed. Its surface may be

plane, or may have the appearance of being ridged. In some cases the process

206 INSECTS OF SAMOA.

is longer than the tibia, and very narrowly channelled on the upper surface, with

the edges uniformly serrate.

Text-Fic. 15.—Hind tibiae of :—(e) Paradibolia indica; (f) Dibolia occultans ; (g) Megistops

quadrinotatus ; (h) Argopistes biplagiata ; (i) Pseudodibolia picea ; (j) Sphaerophyma simona

(k) Sphaerophyma insularum. Figures h, 7, and 9 are of left legs, the others of right legs.

z indicates the inner margin, o the outer.

The above observations are drawn from the following species :

(1) Diboloides bicolor Jacoby, Proc. Zool. Soc. Lond., p. 553, 1897. 8. Africa :

Mashonaland (Text-fig. 14a).

(2) Dibolosoma quadripustulata Jacoby, ibid., p. 560, 1897. Madagascar

(Text-fig. 140).

CHRYSOMELIDAE. 207

(3) Aphthonoides * Jacoby, Ann. Mus. Cw. Genova, xxii, p. 59, 1885. Java,

Sumatra, Japan (Text-fig. 14c).

(4) Serraphula aenea Jacoby, Proc. Zool. Soc. Lond., 1897, p. 557, 1897.

S. Africa : Mashonaland (Text-fig. 14d).

(5) Paradibolia wmdica Baly, Trans. Ent. Soc. Lond., p. 31. 1875.

India (Text-fig. 15e).

(6) Dibolia schilling Letzner, Ubers. Verh. Schles. Ges., 1846, p. 82, 1847.

Kurope.

(7) Dobolia occultans — Koch, Ent. Heft., u, p. 23, 1803; Latreille in Cuvier

Regn. Anim., nu. ed., v, p. 155, 1829. Hurope (Text-fig. 15/).

(8) Megistops quadrinotatus Boheman, Hugenes Resa, Insecta, p. 187,

1859. California (Text-fig. 159).

(9) Argopisies brplagiata Motschulsky, in Schrenck’s Reisen Anvur-Land,

u, Lief 2, Col., p. 236, 1860. Amurland; Japan (Text-fig. 15h).

(10) Pseudodibolia picea Jacoby, Biol. Centr.-Amer., Col., vi (1), Suppl.

p. 291, 1891. Mexico (Text-fig. 152).

(11) Sphaerophyma simon Baly, Jour. Linn. Soc. Lond., xii, p. 479, 1878.

Queensland: Rockhampton (Text-fig. 15y).

(12) Sphaerophyma insularum Maulik. Samoa (‘Text-fig. 15h).

ANALYTICAL TABLE.

1, Anterior coxal cavities closed behind . Stay

Anterior coxal cavities open behind. a iet

2. Tibia longer than tarsus; extreme apex of

tibia rounded, emarginate on each side ;

inner lateral edge without serration except

towards apex, outer lateral edge serrate ;

process a slightly curved rod with blunt

apex, much shorter than first tarsal seg-

ment; claws strongly appendiculate . Duboloides Jacoby (Text-fig. 14a).

* The preparation was made of a leg irom a Japanese specimen collected by G. Lewis,

which was known to Jacoby and no doubt belongs to this genus.

j Latreille in erecting the genus Dibolia cited two species, namely, Altica (Haltica) echvi and

A. (H.) occultans. Since the former belongs to the genus Longitarsus, the latter is designated as

the genotype of Dibolia. The earliest descriptions of these species occur in Hntomologische Hefte,

li, pp. 52 and 23, 1803. The authorship should be ascribed to four people whose names appear

at the end of the preface to Entomologische Hefie, Heft i, without any indication as to who was

actually the writer of the descriptions. These names are Hofimann, Koch, Miiller, and Linz.

In Magaz. f. Insektenkunde, vi, p. 50, 1807, however, Llliger states that Koch was responsible

for the descriptions of the species in Ent. Heft., at least certainly those of the Halticine.

Iv. 3 3

208 INSECTS OF SAMOA.

Tibia as long as tarsus ; lateral edges of tibia

bristly towards apex, outer edge serrate

near apex ; process a small, plain, pointed

rod, much shorter than the first tarsal

segment. . Dibolosoma Jacoby (Text-fig. 145).

3. Tibial process axteudrdinarity jog and shaped

likeasaw . : 4.

Tibial process not so long and not saw- ike sues

4. Process about thrice as long as tibia, which is

much abbreviated ; upper surface of pro-

cess very narrowly concave, with both

lateral edges uniformly and finely serrate ;

apex somewhat flattened ; tarsus as long

as process, first segment longer than

following three segments together, second

segment very small, somewhat broad,

bilobed segment with slender lobes, claw-

segment somewhat thickened ; points of

origin of process and tarsus not near

together, process arising from apex of

tibia, and tarsus from near base of latter ;

tibia accordingly modified . : . Aphthonoides * Jacoby (Text-fig. 14c).

Tibia somewhat longer than either process or

first tarsal segment, which are about equal

in length ; extreme apex of tibia rounded ;

lateral edges plain, without teeth, serra-

tions or bristles, except a few at tip ; pro-

cess with upper surface concave and lateral

edges toothed ; second segment of tarsus

long, but somewhat shorter than first ;

lobes of bilobed segment slender ; claw-

segment long : . Serraphula Jacoby (Text-fig. 14d).

5. Extreme apex of hind tibia ee stnet

produced . 6.

Extreme apex of hind tibia distinctly Sa.

duced : Os

6. Tibial process deeply cleft at apex : ne als

Tibial process emarginate at apex; process

broad, about half as long as first tarsal

segment ; lateral edges of tibia without

serrations or teeth, outer edge undulate at

apex . : ; ; ; : . Paradibolia Jacoby (Text-fig. 15e).

* Jacoby’s original account (loc. cit.) of the tibial characters does not agree with the present

description, which is taken from an example seen by him. It may be remarked that the relative

arrangement of tibia, tarsus, and spur, as seen in this genus, differs from that found in other

genera studied here.

CHRYSOMELIDAE. 209

7. Tibial process comparatively broad, with its

upper surface somewhat concave, and its

length more than half that of first tarsal

segment ; tibia with imner margin without

teeth,* and outer margin with teeth for

about half itslength . : . Dibolia Jacoby (Text-fig. 15/).

Tibial process very deeply cleft, slightly

shorter than first tarsal segment ; lateral

edges with very minute serrations and

bristles only near apex . ; . Megistops Boheman (Text-fig. 159).

8. Femur with ventrally situated blunt process ;

tibial process very small, with bluntly

pointed apex; apex of tibia acuminate ;

lateral edges without serrations. . Argopistes Motschulsky (Text-fig. 15).

Femur without such process : 9:

9. Apex of tibia narrowly produced into a pn:

late process; outer lateral edge of tibia

-with serrations and emarginations, and

with strong bristles near apex ; tibial spur

small and pointed . : : . Pseudodibolia Jacoby (Text-fig. 157).

Tibia comparatively short, broad, end pro-

duced into a point at apex ; tibial process

large, slightly shorter than first tarsal seg-

ment, bluntly pointed, with surface

ridged ; lateral edges of tibia with wide

emargination near apex. : : . Sphaerophyma Baly (Text-figs. 15), k, and 16).

In his generic diagnosis Baly writes: “ Acetabulis anticis integris.” I

have, however, examined the genotype in the British Museum, and find that the

Text-Fie. 16.—Anterior coxal cavities of Sphaerophyma simoni.

anterior coxal cavities are quite open behind ; in fact, so widely are they open

that there cannot possibly be any doubt on the subject (cf. Text-fig. 16).

* This is in a preparation of D. occultans, but in a preparation of D. schillingi a few teeth

are visible on the inner margin at the apex.

310 INSECTS OF SAMOA.

In the case of each genus, with the exception of Megistops, Dibolia and

Argopistes, I have examined the genotype. With regard to Megistops and

Dibolia I have examined specimens determined by Baly, and have accepted

Ogloblin’s determination of Argopisies biplagiata Motschulsky. The genus

Argopistoides Jacoby (Ann. Mus. Civ. Genova, xxxii, p. 931, 1892) should have

been included in the present study, but I have no means of examining the geno-

type, in which, according to Jacoby, the posterior tibia is deeply sulcate in the

apical portion and armed with a robust double-pointed spur.

This study of the tibial characters is not exhaustive, but sufficient to show

beyond doubt the relationship of the Samoan species, and incidentally it indicates

a line of research which could be pursued in order to show the variety of structure

in correlation with the jumping habit of Halticinae.

In the above table the characters presented by the hind tibia and tarsus,

etc., are stated in a comparative manner, and, by means of them alone, it is not

intended here to establish relationships among the genera dealt with.

HISPINAE.

16. Promecotheca reichei Baly.

Promecotheca reichet Baly, Trans. Ent. Soc. Lond., p. 374, 1869.

Promecotheca lindingert Aulmann, Entom. Rundschau, xxxi, pp. 27, 28, 1914.

Upolu: Mulifanua, 16.vii.1925, 5 examples; 17.vu.1925, 2 examples

(Wilder).

Tutuila: Pago Pago, 3,000 ft., iv.1918, 1 example (Kellers) ; 1,000 ft., 1

example (Kellers).

[During 1924, 1925, we looked carefully for this species in many parts of

Samoa; the only specimens we found were on a coconut-palm at Mulifanua,

Upolu, in November, 1925. This is remarkable, since Aulmann has recorded

it as a pest, though he gave no details.—P. A. B.]

It may be recorded here that an example from the Deutsches Entomo-

logisches Museum, Berlin, sent to me by Dr. Walther Horn, is from Savaii.

Although the specimen is not perfect, I do not hesitate to identify it as P. reecher

Baly. Specimens are known from Tonga, Fiji, and elsewhere.

Instribution of the Genus.—The genus Promecotheca, first described in 1853,

by Blanchard, from a specimen taken in Tonga, has representative species in

Fiji, New Hebrides, Solomon Is., New Pomerania, New Guinea, North Australia,

CHRYSOMELIDAE. 211

Borneo, Java, the Philippine Is., and China. The distribution of the species

of this genus, so far as the food plants are known, depends on that of the coconut-

palm, upon which these insects feed, the larvae living in the folds of the unopened

tender leaf-buds. It is to be expected that species of Promecotheca will be found

to occur wherever the coconut-palm is cultivated.

DESCRIPTION OF THE Larva oF Promecotheca reicher Baty

(Text-figs. 17 and 18).

The following description is taken from a microscopical preparation of an

example from the Fiji Islands, sent by Mr. H. W.

Simmonds.

The larva (Text-fig. 17) is elongate, flattish,

broadest across the mesothorax, and thence

regularly diminishing in breadth, towards the

posterior extremity, the last abdominal segment

being the narrowest. It measures slightly less

than 4 mm. when fully extended after treatment

in potash. The body is composed of thirteen

segments including the head; in addition to

the three thoracic and nine abdominal segments,

a fourteenth segment is represented by the anal

sucker. The prothorax is narrowed in front,

and has rounded sides. The mesothorax is

much shorter than the prothorax ; its sides are

uniformly rounded without any lobes, and it is

much broader than long. The metathorax is es

similar to the mesothorax. The abdominal seg- / a al =

ments are much broader than long; the sides of

each of the first seven are somewhat produced J, Se

so as to form a lobe; those of the eighth and Cs.

ninth are less produced. On or near the lobes |

there are several fine bristles, which are most ,

numerous in the case of the eighth and ninth

segments. The upper and lower surfaces of the

whole body are shagreened ; those portions of paye-wcg. 17—Larva of Prome-

the prothorax that are produced to the bases of cotheca reichet, ventral view.

212 INSECTS OF SAMOA.

the labrum and labium have their surfaces very strongly reticulate; on the

abdominal segments the central areas are more definitely shagreened, and this

condition is much more conspicuous between the eighth and ninth segments

(Text-fig. 18b). The shagreened surfaces no doubt facilitate the movements of

the larva in its burrow. ‘There are nine pairs of spiracles, of which one pair is on

the mesothorax, each spiracle being situate anteriorly on one side and opening

somewhat ventrally. The other eight pairs are on the first eight abdominal

segments, each spiracle similarly occupying a lateral position but opening some-

what dorsally. In the present preparation all the spiracles can easily be traced

by means of the portions of tracheae attached to them. The larva is devoid of

legs, and I cannot trace any indication of rough or papilliferous surfaces at

pomts where they should normally be found, unless the clusters of dots indicated

by X in Text-fig. 17 are to be considered as such.

Although the present specimen appears to be nearly full-fed, this is

probably not the case; nevertheless the structural details are doubtless the

same as in a full-fed larva.

Anatomy of the larval head (Text-figs. 17, 18a, }, c).

The head (Text-fig. 18a) is of the type usually found in larvae which are

borers or leaf-miners. It is formed by a large chitinised plate, which is deeply

divided into two elongate lobes and has the shape shown in Text-fig. 17 (J). There

are strongly chitinised ridges acting as supports along the middle, and the

whole head is imbedded in the prothorax except its anterior edge, each side of

which is rounded, bearing an antenna, the middle portion being occupied by the

mouth-parts. The buccal cavity is formed by labrum or upper membranous

structure, the two mandibles and the labium or lower lip. The labrum is

reinforced by a chitinous support along the middle ; at its anterior edge and on

the sides there are numerous papilliform bristles forming a brush-like structure.

The mandible is triangular, its inner side being produced into a convex sharp

edge without any teeth. The labium is membranous, deeply cleft in the middle

and thus divided into two rounded lobes. Along the edge of each lobe there are

numerous papilliform bristles. On each side of the labium a rather long and

pointed palpus is visible. Situated on the upper edge of the exposed portion

of the head and externally to the mandibles are the antennae. Each antenna

is composed of three segments, a basal, a median and an apical ; the basal seg-

CHRYSOMELIDAE. 213

ment is large; on the inner side of the median segment is an erect, fairly thick

lobe; the third segment is situated a little to the outside of the longitudinal

axis of the second, and bears seven papillae or hairs, as shown in Text-

fig. 18c.

Text-Fic. 18.—Larva of Promecotheca reichei :—a, mouth parts, from below: md, mandible;

lb, labium; p, labial palp. b, seventh, eighth, and ninth abdominal segments, from below.

ce, right antenna.

Triangular Structures (‘Text-fig. 186).

In the present preparation a series of triangular structures is visible between

the last two abdominal segments, appearing to lie between the dorsal and ventral

surfaces of the body. In the absence of further material, there has been no

opportunity of dissecting a larva, and thus throwing more light on the nature of

these structures.

214 INSECTS OF SAMOA.

CASSIDINAE.

17. Cassida strigula Montrouzier.

Upolu: Apia, vill.1924, 5 examples. Aleipata, Lalomanu, xi.1924, 1

example. Siumu, 26.xi.1923, 1 example (Armstrong).

Tutuila : Eastern end of island, 1,070 ft., 21.vi.1918, 4 examples ; 1,000 ft.,

25.vil.1918, 1 example; 1,000-2,000 ft., xu.1918, 1 example; 760-900 ft.,

iv.1918, 3 examples (Kellers). Fagassa, 9.1x.1923, 4 examples. Leone Road,

7.1x.1923, 1 example. Pago Pago, 24.ix.1923, 4 examples (Swezey and Wilder) ;

14.x11.1925, 1 example.

In the British Museum Collection there are two examples collected in

Samoa between March and August, 1921, by Dr. F. W. O’Connor ; one of these

has been examined by Dr. F. Spaeth. ‘There are others from N. Australia: Port

Darwin, 2 examples ; Groote Hylandt, 27.1.1925, 1 example (G. H. Wilkins).

Mr. P. A. Buxton tells me that the Samoan specimens were found on sweet

potatoes, and it is evident that the species has been introduced by commerce.*

In the Coleopterorum Catalogus (Junk and Schenkling, Berlin, 1914) Cassida

strigula Montrouzier is treated by Spaeth as a subspecies of C. diomma Boisduval,

which occurs in New Guinea. Herein Spaeth is quite possibly correct, especially

in view of the great variation in the colour pattern of these beetles.

My reason for including this species in Cassida instead of in Metriona is

stated in my book, “Fauna of British India, Coleoptera, Chrysomelidae

(Hispinae and Cassidinae),” pp. 362-363, 1919.

* It is possible that the introduction took place centuries ago. Sweet potato

(‘‘ Kumara”) was used as food by the Polynesians before the white man entered the Pacific.—-

P. A. Buxton.

CO CO AD OF OO DOH

CHRYSOMELIDAE. 215

LIST OF TEXT-FIGURES.

. Aprionota lucida, sp. n. X 24.

. Pycnophthalma tutuilana, sp. n. x 30.

. Stygnobia aenescens, sp.u. X 11.

. Stygnobia cauta Weise. 12.

. Stygnohia variabilis, sp. n. X 18.

. Stygnobia minuta, sp.n. X 26.

. Stethotes rufonigra, sp.n. X 22.

. Plagiodera samoana, sp.n. X 9.

. Aulacophora nigrobrunnea, sp.n. 10.

. Coxal cavities of Plesistia brunnea.

. Plesistia brunnea, sp.n. X 9: a, claw.

. Nesohaltica nigra, sp. nu. X 30.

. Sphaerophyma insularum, sp.n. X 14.

. Hind tibiae of :—(a) Diboloides bicolor ; (b) Dibolosoma quadripustulata ; (c) Aph-

thonoides sp.; (d) Serraphula aenea. 7 indicates inner, 0 outer margin of tibia.

. Hind tibiae of :—(e) Paradibolia indica; (f) Dibolia occultans; (g) Megrstops

quadrinotatus ; (h) Argopistes biplagiata ; (i) Pseudodibolia picea ; (j) Sphaero-

phyma simon; (k) Sphaerophyma imsularum. Figures h, 7, and j are of left

legs, the others of right legs. 7 indicates the inner margin, o the outer.

. Anterior coxal cavities of Sphaerophyma simoni.

. Larva of Promecotheca reichet Baly, ventral view.

. Larva of Promecotheca reichei :—a, mouth parts, from below: md, mandible ;

lb, labium; p, labial palp. b, seventh, eighth, and ninth abdominal segments,

from below. c, right antenna.

PRINTED IN GREAT BRITAIN BY WILLIAM CLOWES AND SONS, LIMITED, LONDON AND FECCIES,

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INSECTS OF SAMOA

AND OTHER SAMOAN TERRESTRIAL

ARTHROPODA

LIST OF PARTS AND SYSTEM OF PUBLICATION —

Pat I. Orthoptera and Dermaptera.

-,,. Il. Hemiptera.

aye ae UB Lepidoptera.

» 1V. Coleoptera. —

‘i : | V. Hymenoptera.

tae.yee V1. Diptera.

eae: VII. Other Orders of Insects.

_,, VIII. Terrestrial Arthropoda other than Insects.

_ 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.

Meeves 2

INSECTS OF SAMOA

AND OTHER SAMOAN TERRESTRIAL |

ARTHROPODA

Fasc. 2. Orthoptera. By Dr. L. Chopard. 51 text-figures. Pp.9-58. 1929, 4to. 5s.

“List of Fascicles issued to 23rd February, 1929 : Pe sere fe

Insects of Samoa and other Samoan Terrestrial Arthropoda. Nees 1 and Date Issued.

2 (in envelope). 1927, 4to. 6d. 26th February, Mees Bee

Parr I. OrtHoprerA AND DERMAPTERA. _ . GAwis

Fasc. 1. Dermaptera. By Dr. Alfredo Borelli. Pp. 1-8. 1928, 4to. Is. 28th Tale 1928, st

Part I]. HEMIPTERA. _ i

Fasc. 1. Fulgoroidea. By F. Muir. 25 text-fieures. Peyliide (Chaveida), _ By i

Prof. D. rawford. 4 text-figures. cide, Aphidi ae

leyrodide.

By F. Laing, M.A., BSc. 3 text-figures. Pp. 1-45. ara

Fase. 2. Cercopide. By V. Lallemand, M.D. 10 eeehedre * Geadide. By

.G. Myers, Sc.D. 22 text-figures. "Aquatic and Semi-aquatic pose.

sy Prof. Teiso Esaki. 6 ce Pp. 47-80. 1928, 4to. 2s. 6d 5

Part III. Lepmoprera.

Fasc. |. Butterflies of Samoa and some nei el peel Island- ote: By G.H.E

Rope M.A., F.E.S. 1 text-figure an lates grou 1927, 4to. 5s.

Micro-Lepidoptera By Edward Meyrick, Ha, FERS. Pp. 65- 116.

1927, 4t

By Louis B. Prout, F.E.S. 2 text-figures and ! plate.

1927,

Fasc. 3. Geometridae.

Pp. 117-168. 1928, 4to. 2s. 6d.

Part IV. CoLzopTERA.

Fasc. |. Carabide. By H. E. ie.

Zimmermann. 2 tex fetes

figures. Hydrophilide.

a fox Beures

Ad Oe aylinid #. By eau MB. 2 text-

Ir yinont Pasa re Clavicornia and

Lamellicornia. By wees text-fi

Fae 2. Heteromera, Bostrych oidea, Malar nata fe Bie By K. G.

Blair, B.Sc tee heats: Elateride. - van

a Mel pee Nannie

ie. late. Brent \idae. By R. Ki

RAB Kare Ae PAD. fi exe fear

R. i ie te. By DSc., Pp. 67-174. ie 4to. 5s.

Fasc. 3 roscide.

; Blair, B.Sc. text-figure.

By S. Maulik, M.A. 18 text-figures. Pp. 75-218

Part ‘ eNO

Fase. 1. peor hecoiles, and Vesppidea: By RC

Sia Evelyn C Chen RES ETS I eae Fe

By Francis illiams. 12 text-figures, Formicide. ey

lemme. 4 text-figures

1929, ae

p ae

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

Part VI. Drprera.

Fasc. 1. Streblide and Nycteribiide. By L. Falcoz. 7 He ese

boscides, By G. F. se - text-figures. Pp. 1-21. 1927, 4to. 2s. 6d.

sc. 2. Nematocera. . Edwards, M.A. aoe ie Se seen

ear her BA PED atone: Pp. 23-108, 1928, 4to..

Part VII. Orsner Orpers oF INsEcts

Fasc. 1. Isoptera: es Saree oe Gerald F. wee

I plate. Odonata. y Lt.-Col,

Pp. 1-44. 1927, Ses

Fasc. 2. ee Bi), Menus ay D. (Cantab) ERS,

Lestage. 2 text-f oe phonaptera.

By cha Bagnall, Sgt pire "hai eats

ay 4 Wallootgs By Lids wire DSc... 2 text-fig res Anoplura. By

“ Bapeniee “MLA. i richoptera. : y rtin E peel . figure.

are y P en-retersen. text-figure an ates terygota.

Be Terie. 1928, are

and J. A.

Thysano tera.

Pp. 45-76. 1928, 4to.

By George H. Carpenter, D. Sc, 32text-figures. 2s. 6d,

Part VIII. Terrestrra, ARTHROPODA OTHER THAN INSECTS.

Fase. 1, Isopoda Terrestria. By Harold G. Jackson, DSc. 2 plates. Scor-

eis ea. By P. uxton, M.A. Pseudo-scorpiones. By A. Kastner. |

Bee eres Acarina. By Stanley Hirst. 2 text-figures. Pp. 1-27.

23rd Janes 1928.

| ae April 1927,

28th Mag, 1927.

24th March, 1908,

Dynes. By A.

927, 4to. 3s.

Bie Zwaluwenberg. 10

By Fleutiaux: Cerambycide. By —

Proterhinide. ‘By Ne

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L. Perkins, L Doe ;

Pigs:

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raser, € Bure Se 28th May, 1927. |

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25th ae 1927.

ee December, 1927. ;

25th Faber 1928.

23rd Febrae 1929

25th Fi sary, 1928

23rd July, 1997 :

23rd June, 1928,

23rd June, 1928, i

28th July, 1928