PROCEEDINGS

OF THE

BIOLOGICAL SOCIETY OF WASHINGTON

NEW ^{RECENT CRINOIDS FROM THE} INDIAN OCEAN.

BY AUSTIN HOBART CLARK.*

At the

suggestion ^of

Dr. F, A. Bather, the Indian Museum has entrusted

to

me

for

study

^the

magnificent

^{collection of recent} crinoids

brought

together as

a

result of

the operations

^of

the Royal ^Indian Marine Surveying Steamer

Investigator.

Covering

asit

does

the region

from

the

Malay ^Peninsula

^tothe

^Persian

Gulf, the collection ^is

one

of

extraordinary

interest, for

by

^{its aid the}

westward extension

of

many East Indian genera can be

^accur- ately traced,

and

it is possible ^to

form

a

very

^clear

concept

^of the progressive

diminution

in intensity of

the wonderfully

^rich

East Indian fauna

^as

one

travels

westward.

Most

of

the

species in the collection are

represented by

large series,

and

there is

an

astonishingly

complete

representation of those

very small forms

so

common

in

the

East,

which

are frequently

disposed

^{of in}

published

reports as

"unidentifiable young,"

graphically

bringing out

^the

thoroughness with which

the collectors ofthe Investigator

performed

their labors.

I

wish

to

record my

appreciation ^of the great

kindness shown me _by Dr.

F.

A. Bather and Dr. N. Annandale

of the

Indian

Museum

in entrusting^to

me a

collection of

such

_great interest

and importance

^{as isthat of}

the

Investigator.

The complete

report

upon

^{this collectionwill}

be published by

the

Indian Museum

in their series of

monographs dealing with the Indian fauna.

Family ZYGOMETRlDiE.

Genvs EUDIOCRINUSp.H. Carpenter.

Eudiocrinus

minor

_sp. nov.

Type.

—

Cat. No. 71B

=

_^Y"^ Indian

Museum,

^{from the}

Andaman

Islands.

*Published with the permission of the Superintendent of tlie IndianMuseum, Calcutta.

11—Proc. Biol.Soc.Wash.,Vol. XXII,1909. (76)

*l

^Jf

76

Clark

— _New

Recent Crinoids

from

^the

Indian Ocean.

Ceiitro-dorsal a thin _disk,the bare^flatdorsal pole ¹

mm.

indiameter;

cirrussocketsarranged ^inasinglemarginal ^row.

Cirrixii, 12, 5

mm.

long; ^firsttwo_joints twiceasbroad _{as long,}third halfagainas l)road as long,fourth twiceaslong^asbroad; followingjoints very gradually decreasingⁱⁿlength,^tiie antepenultimatel:)eingaboutone- third again^as long^asbroad; ^third

and

fourth_jointsstrongly

"

dice-ljox shaped,"^fifth

and

sixthsliglitly so,the following with i)nicticallystraiglit edges; ^cirriproximally almostrcjund in cross-section, afterthefifthjoint

becoming

laterallycompressed,

and

thereforel)roader in lateralview;

no

dorsal spines or projections; opposingspine median,small, scarcely equal- ing one-fourth^tlie diameterofthepeiuiltiniate joint in height.

Arms and

_pinnules as inEudiocrinusoriiatus, the overlappiiig^of the brachials

and

_pinnularsbeing moderately

marked; arms

¹⁵

mm.

_long.

Color (inspirits).

—

_White.

Family HIMEROMETRID.E.

Genus

DICHKOMETRA

A.H.Clark.

Dichrotnetra

aranea

sp. nov.

Type.—

^{Cat. No.}

^V^

^Indian

Museum,

^{from 8°51^.30'^N.} lat.,81°

IK

52^'E. _long.; 28fathoms.

This

new

formisnearesttoD._finschiifrom

New

Britain; itdiffersfrom thatspeciesⁱⁿhaving

somewhat

fewercirrus joints(o;>-6(i),

and

inhaving Ps nearly or quite^aslongas P2,while the_{joints in}thedistalportion^ofthe proximalpinnules are

much

elongated, instead^ofsubequal,slightlylonger than broadas in finschii.

The

lowerpinnules arecomparativelyslender, Vjut sliglitly stiffened; P2^isaboutasstout_{as Pi,}

and

2

mm.

_longer.

Color (inspirits).

—

_Lightbrownish_yellow.

Genus

CYLLOMETRA

A.II.Clark.

Cyllometra

^mollis sj). nov.

Type.

—

Cat.No. _15F, Indian

Museum,

labeled, with _{a question} mark, Kurrachi.

Centro-dorsal _{discoidal, thin,} the polar area flat, 2

mm.

in diameter;

cirrussocketsarranged ⁱⁿone

and

a

more

orlesspartialsecondcrowded row.

Cirrixx, 20-22, ¹⁰

mm.

long; firstjoint short, second andthird about twice as broad _{as long,} the remainder _{very slightly} broader than _long

becoming

^almost squarish on the terminal five or _six; second

and

fol-

lowingjointswith thedistal dorsaledgeproduced and finelyspinous,^this projection progressively narrowingdistally, at the

same

timevery slowly

moving

^toa

more

_{i)roximal po.sition,} after al)out the eighth

becoming

^a pair ^ofsmallsubterminal_tubercles, which onthe last fivetoseven_joints give i)lace tosmall

median

_{tubercles; opposing spine}

much

_larger than the spinesonthe precetHngjoints,triangular,the_a})exterminaltonearly median,ⁱⁿheightreaching^to one-half or rather

more

of thediameterof

.thepenultimatejoint; terminalclaw_{veryslightlylonger}than _{the penul-}

timate_joint, moderately^stout

and

moderately curved basally,

becoming more

slender

and

lesscurveddistally.

Kadials about even with the edge ^of the centro-dorsal; i

Bn

oblong, aboutthree timesasbroad_{as long,}notincontact basally; iBr2(axillary) pentagonal,about twiceasbroad _{as long,} the lateral edges abouthalf as long ^as thoseof the ⁱ _Bri,

making

^with

them

a veryobtuse angle^{; i}

Br

series

and

lowerbrachials with a_slightlyindicatedrounded

median

cari- nation.

Arms

10, 65

mm.

long, resembling ^{thoseof C.} informis,^to which this species^is

most

closely related.

Pf, absent; Pi small

and

_weak, 4

mm.

_long with fourteen _joints,the first short, the second _squarish, the following gradually increasing ⁱⁿ length,

becoming

^twiceaslong^asbroad_{distally;joints in}thedistalthird with the distal edges

armed

with fine spines; P2 13

mm.

long,stouter tliau Pi, though ^{of the}

same

proportions,with seventeen _joints,

which become

_squarish at the third

and

twice as long ^as broad terminally;

second

and

following withafew_spines

on

thedistaledge; P3 6

mm.

_long,

basally^asstout_{as P2,} but nottapering sorapidly,

and

thereforelessdeli- cate distally, withfifteen joints, thedistalelongated; Va4

mm.

_long, not so delicate as Pi, with ten _joints; Pe 3

mm.

long, following pinnules increasing slowly ⁱⁿ length, the distal pinnules being ⁷

mm.

_long,

slender,with_{elongatedjoints.}

Coloi' (inspirits).

— _Brown,

_theperisomedarker.

Family TROPIOMETRID^.

Genis

CALOMETRA

a. H.Clark.

Calometra

_{magnifica sp.} nov.

Type.—Q-At. No.

15A =

_^V-^Indian

Museum; Malay

Archipelago, 160 fathoms.

Centro-dorsal hemisi^herical, the bare polar area convex, ²

mm,

in diameter; ^cirrus socketsarrangedⁱⁿtwoor three _closelycrow^ded irregu- larmarginal ^rows.

Cirri xx, 41-48, 40

mm.

_long; first cirrus joint short, the next

two

abouttwiceasbroad_{as long,} the following gradually increasingⁱⁿlength tothefifthor seventh, which^isabout one-third broader than _long; fol-

lowingjointssimilartoalmost the middle of the _cirrus, at

which

_point they begin^todecrease graduallyⁱⁿ length, being ^{twice as} broad as long intheterminal portion; atabout_{the eighthjoint} the

median

_portion of thedistaldorsaledge begins ^to project ⁱⁿ a small

A

_{-shaped spine;} this very slowly increasesdistally,thewholedorsal surfaceofthe_jointbecom- ing rounded-earinate

and

_rising

somewhat

atthe

same

time, until in the terminal third the cirrus joints bear broad spatulate carinate processes, equal ⁱⁿ height ^to about one-third their diameter; opposing spine ^tri- angular, similarⁱⁿ shape

and

size to the spineon the preceding joint, blunt, theapex terminal, arising from the distal two-thirds of the pen- ultimatejoint, about _equal to halfthediameter of the penultimate joint in height; terminal claw _conical, equal ⁱⁿ length ^to the penultimate joint, stout, slightlycurved.

78

Clarh

— _New

Recent Crinoids

from

^the

Indian Ocean.

Disk _completely covered with a

pavement

^{of rather small rounded}

plates,those inthe_{angjles of}the calyx hetweenthedivision serieshearing conical processes^intheircenters; ^this calcareous covering ^is not _closely united tothe perisonie heneath, except along ^the amhulacra, but draws

away

^{from itin}drying; amhulacrawith side

and

_{covering plates highly} developed.

Ends

ofthe basal rays^{visible as} small, though prominent, ^{tubercles in} the angles^ofthe calyx^{; radials}even withthe centro-dorsal, butover the ends of the basal rays extending

upward

^{in a}

narrow

_{slightly wedge-} shaped (base

upward)

process, which terminates distally in a spatulate processbetween thelateraledges^of theiBra; ⁱ

Bn

short, slightly trape- zoidal, notincontactbasally, aboutfour times as broad _{as long,} rather strongly convex _dorsally, with a rather prominent

narrow

rounded

median

_ridge;ⁱBrs (axillary) i)eiitagonal, nearly or quite twice^asbroad as long, thelateraledgesslightlyshorterthan those of thei

Bn, making

with

them

anobtuse angle, witha

narrow

rounded

median

ridge similar to that

on

the iBri in the proximal half; ⁱⁱ

Br

_2, with the rounded

median

_ridge

much

less))rominent than onthe ⁱ

Br

series.

Twenty arms

^{about 12U}

mm.

_long; firstbrachial small, wedge-shaped, twice as broad as long exteriorly, almost _entirely united _interiorly;

second brachial considerably larger, irregularly quadrate, ^botli usually with aslight trace ofarounded

median

_keel; third

and

fourth brachials (syzygial pair) oblong, ^halfagain^as broad as long; next four lirachials oblong, twice^asbroad_{as long,}with alowtubercle in the proximal ^half of the

median

line; following two or three l)rachials wedge-shaped, ^the following triangular, about as long ^as broad;

arm

_tips not preserved.

On

the lower _i)artof the

arm

traces of tubercles are found on alternate sides ofthe

median

line; theproximal ^{third ofthe}

arm

is

somewhat com-

pressedlaterally,

and

bearsoneither side a shallow lateral groove.

The arms

increase slowly ⁱⁿdiameter

up

^toaboutthe twelfth brachial; from the fourth

onward

the brachialshave moderatelyi)rojecting finelyspinous distal edges. Syzygies occur between the third

and

fourth _brachials, again betweenthe eighteenth

and

nineteenth _(rarelythe seventeenth

and

eighteenth or twentieth

and

twenty-first),

and

distally at intervals offour tonine (usually^sixtoeight) oblique nuisculararticulations.

Pi8

mm.

_long, slender

and

weak,^with twenty joints, the first broad, slightlywedge-shai)ed,^al)outtwiceasbroadasthe length^{of its} proxinuil edge, produced distally into a high rounded carinate process; second joint longer, halfagain^asbroad_{as long, bearing alarge fan-shaped}cari- nate processwitha scalloped or dentate ^distal edge; third

and

fourth considerably ^lessindiameter than the second, slightlylongerthan_broad, with _strong oblong ^carinate pnjcesses; following joints non-carinate, slowly increasing ⁱⁿ length,

becoming

^{twice as} long ^as broad in the terminal portion^{; after} the second _joint the _i)innule ^is rather _shari)ly triangular; ⁱⁿthedistal half the_{joints jjroject}

somewhat

over the bases ofthe succeedingjoints atthe angles^ofthe prism, ^thisincreasingtoward the_tip

where

theendsofthe_jointsoverlap ^all around

and

are

more

or less spinous; ^{I'.- 14}

mm.

lung, slender, but slid', with twi'uty-one joints;

firstjointbroad, abouttwiceaswideasitsproximaldiameter, roundedly carinate _distally; second _joint wedge-shaped, about ^as broad as long proximally, with a thin carinate process about twice as broad as high distally^; third one-third longer than _liroad, strongly carinate distally, butthecarination not quite^sohigh^asthatonthe precedingjoint^; fourth twiceaslong^asbroad, carinate distally like the third; following joints about two

and

one-lialf times as long ^as broad, slightly longer ⁱⁿ the terminal part ^; the pinnule^isstronglystyliform,the_jointsbeing

more

or lessproduced anteriorly^atthe angles^oftheprism ^{in the}shape ^ofa spine overlapping ^{the bases of the} succeeding joints^; the distal ends of the joints are

somewhat

_prominent

and

_finely spinous, ^this

becoming more

pronounced distally^; Ps¹⁵

mm.

_long,similarto P2, thoughveryslightly stouter; P4 1-1 nun. long; P5 ¹²

mm.

_long; Pe 10 nun. _long,similar to P3, but with proportionately

somewhat

_longerjoints,

which

ⁱⁿ the distal portion have

more expanded

ends; Pr, has fifteen joints; P7 10

mm.

long, slightlystouterthan Pr,, with about the

same number

of joints, which are proportionately rather shorter; Ps ⁹

mm.

long, stouter than P-, especiallyon the _third, fourth

and

fifth joints,

none

of which are

more

thantwiceaslong^asbroad; following pinnules^of the

same

_length

and

in general similar^; the third

—

_{seventh joints} are

somewhat

broad- ened, thepinnuletajieriugevenlyfrom aniaxinuun width

on

the fourth toa slender tip, with

nmch

_{elongate joints} wdiich have

expanded and

spinous^distalends; ^distalpinnules slender, 10

mm.

_long.

Color(inspirits).

—

White.

Calometra

spinosissima sp. nov.

Tijpe.—C&i. No. 13B

=

_^V-*^ Indian

Museum;

^{from the}

Andaman

Islands.

Centro-dorsal discoidal, moderately thick, the bare polar area flat,3

mm.

indiameter; ^cirrussockets arranged ^{in a}single crowded marginal row.

Cirri moderately slender, xi, 42-55, 25

mm.

_long ; first joint about three timesasbroadas long,the following slowly increasingⁱⁿlength ^to the sixth or seventh,

which

is nearly^aslong^as broad, then_reiBaining similarto the twelfth or_fifteenth, then _verygradually decreasing^sothat the_{joints in}theterminal portion are twice^asbroadaslong ^;ataboutthe fifteenth jointalow sharp ^{dorsal keel}

makes

its appearance, ^{at first in} the distal portion only, but soon _{along the} entire dorsal surface,

which

very slowly increases ^{in iieiglit,} becomingvery prominent on ^{the short} terminal joints,though never exceeding

more

thanone-fourththeirdiam- eter inheight^; opposing spine andterminalclawas in

C

multicolor, to which formthis species^ismostclosely related.

Disklacking; ^side

and

_{co\eringplates}very highlydeveloped along^the brachial

and

piruiuleambulacra.

Ends

ofthe basal rays^{visible as}smallrhombicareasinthe angles^ofthe calyx,but notraisedabovethe general surface ^of the _radials,

and

there- forenotespecially ol)vious; radialsshortinthe

median

line, but extend- ing

up

^intothe angles^of the calyxⁱⁿtheformof

an

equilateral triangle,

80

Clark

—

_Neiv

_Recent

_Crinoids

_from

the

Indian Ocean.

tliorounded apex^ofwhichentirelyseparates the bases^ofthe ⁱBri; ⁱ Bri shghtlytrapezoidal,abouttwice

and

one-halfasbroadaslong, the ventro- lateralmarginsvery thin^{; i}Bro_(axillary) pentagonal,^aslongas, or only slightlyshorter than, broad, the ^lateral edges nearly or quite ^as long ^as those ofthei

Bn,

slightlyconstricted _justbelowthelateralangles;ⁱⁱ

Br

2, thefirstunited intheproximal two-thirds, diverging^atapproximately^a right angledistally.

Nineteen

arms

(in the _tyjie) l.'>0

mm.

long, resembling ^{in the}

main

thoseofC. multicolor.

Pi 10

mm.

long, very slender

and

_weak, with thirty-five joints,the first proportionately very

much

enlarged, twice ^asbroad_{as long,}with a strong carinate process, the second

much

_{shorter, strongly} trapezoidal, the remainder _{very small}

and

_squarish; P2

somewhat

_longer, but stitt"

and

spine-like, with_elongatedjoints likePs; Ps 20 nmi. long, not _espec- iallystoutl)utvery ^stiff, withabout twentyjoints, thefirstaboTittwiceas broadas long, slightly carinate, the second trapezoidal, aliout as broad distally astheproximal length, the third ^halfagain^aslong^asbroad, the fourth over twice aslong ^as broad, the remainder two

and

one-halfto three times as long ^as broad

and

even_{longerdistally} ; the _joints have slightly projecting

and

_spinous distal ends, ^this character increasing ⁱⁿ intensity distally^; P4 similartoP3

and

ofthe

same

length^; the following pinnules decrease^to12

mm.

on _Pe, then

become somewhat

stouter,

and more

slender again distally, though remaining ^{of the}

same

length; the joints in thedistal portion^ofallthe pinnuleshave prominent,

somewhat

expanded, spinous^distal ends.

The

_pinnules

on

the outer

arms

of each ray appear^tobeconsiderably longerthanthose

on

theinner.

Color (in spirits.)

—

_{White, thickly blotched on the}

rays, arms,

and

pinnules with])urple,which color also forms on the rays

and

division seriesa

more

orlessdefineddorso-lateralline.

Family THALASSOMETRID^.

SubfamilyTHALASSOMETRIN.E.

Genvs

CROTALOMETRA

a. II. Clark.

Crotalometra

rustica _sp. nov.

Type.—

^{Cixi. No.}

19A =

_-»-V-Indian

Museum; Malay

Archipelago, oO fathoms.

Centro-dorsal apparently^{as in C.} magnicirra, with the ^cirrussockets arrangedintencolumns,

two

ineachradial area.

Cirri xx, about 70 ((i!) to broken _tip), 85

mm.

long, large

and

stout;

first three _joints subequal, about three times as broad as long,fourth slightly longer, ^fifth squarish or _slightly longer than _broad, following jointsaboutone-third longer than _broad, afterthe eighteenth

becoming

squarish,

ami

after fourorfive

more

abouttwiceasbroad as long; eigh- teenthatransition joint; afterthetransition joint the dorsal surface of each _{jointgradually}^risestoasul)terniinal dorsal_tubercle,which,however, neverprojects inthef<jrm of a spine; the tubercle^isatfirstratherbroad transversely

and

rounded _dorsally, but _distallyit becomes narrower, so

tliatthe dorsal surface ofthe_jointsbecomesV)hintly carinate.

The

dorsal edge^ofthecirri presents aslightly serrate appearance.

Ends

of the basal rays ^{visible as} prominent dorso-ventrally elongate tnberclesin the angles^ofthe calyx; radialsprojectingveryslightly

beyond

the edges ^of the eentro-dorsal; ⁱBri very short, band-like, above five times as broad as long, convex proximally, concave _distally, in close lateralapposition; iBro _(axillary)broadlypentagonal, halfagain^asbroad as long,^all thesidesstronglyconcave; the lateraledges^of thetwo

com-

ponentsoftheI

Br

seriestakentogether areevenly

and

strongly concave, the proximal width of theiBri

and

the distal width of theiBr2being aboutthesame; Iwth these_joints are sharplyflattened laterally, withthe apposededges

somewhat

everted, ii

Br

4 ₍₃-f 4), very stronglyrounded dorsally ^like theiBr, in close lateral apposition

and

_{sharply flattened,} thelateraledges

somewhat

_produced; thejoints of thisdivisionseriesare proportionally ratherlong.

Twenty arms

about 150

mm.

_{long, deep}

and

compressed, strongly rounded_dorsally; firstbrachial very short,strongly concave _anteriorly;

secondbrachial

much

_largerwitha posterior roundedprocess incising the first; third

and

fourth brachials _(syzygial pair) about as long^asbroad, concave _dorsally

and

laterally likethe iiBrs^4-4; following brachials ^to theninth wedge-shaped, ^half again ^asbroadaslong; following^l)rachials triangular, aboutaslong^asbroad, ⁱⁿ the terminal portion^ofthe

arm

be-

coming

wedge-shaped

and

slightly longer. After theproximal^thirdofthe

arm

the brachials developprominent

and

_spinousdistalends

and

astriated dorsal surface. Syzygies occur between the third

and

fourth _brachials, again between the fifteenth

and

sixteenthtonineteenth

and

twentieth,

and

distally at intervals offourtonine obliquemuscular articulations.

Pxj 15

mm.

long, large

and

stout in the basal_half,then_tapering to a slender _tip, with about twenty-five joints,the second

—

seventh broader than _long, the remainder aboutaslong^asbroad; ^Pi12

mm.

long, with twenty-three joints,

much

less stout thanP^. the outer joints

somewhat

spinous along^theirdorsal ridge^; Ps7

mm.

_long,considerably

more

slender than_P2, tapering evenlyfrom the baseto the

end

of the proximal half, slenderfromthere onward, with^sixteenjoints, ^all but the first two _ap- proximately squarish; following pinnules about the

same

_length, but scarcely tapering ^{at all until} near the _tip, hence appearing

somewhat

stouter ; they are

composed

^{of aboutfourteen}joints; distalpinnules

mod-

erately slender, 12

mm.

_long with twenty joints, the first trapezoidal, abouttwiceasbroaddistally as^its

median

_length,thesecondtrapezoidal,

somewhat

broader _distallythanthe

median

_length,theremainder_slightly longerthan broad;the dorsal ridge^isverysharp

and more

orlessspinous.

Color(in spirits)^.

—

_White.

SubfamilyCHARITOMETRIN.E.

Genus

PACHYLOMETRA

A.H.Clark.

Pachylometra

^macilenta sp. nov.

Type.—Cat

^No.

IG

Indian

Museum;

^10°

^{47M5'^}

^N. lat., 72° 40^ 20^' E. _long.; 705fathoms.

82

Clark

—

_Neiv

_Recent

_Crinoids

from

^the

Indian Ocean.

Centro-dorsal a short truncated cone, moderatelylarge, the bare polar area_flat, 2.5

mm.

ⁱⁿdiameter;^cirru.ssocketsarranged ^intencolunmsof usually

two

each, thecolumns ofadjacent^radialareas_closelycrowded

and more

orlessalternating,thosewithin the

same

radialarea usuallyslightly separatedanteriorly.

Cirrixx, 21-22, 25

mm.

to36

mm.

long,comparativelylong

and

slender;

firstjointveryshort, secondtwiceasbroad_{as long,}third aboutaslong^as broad, following gradually increasing ^to the _sixth, which ^is about half again^aslong^asbroad; nexttwoor threejoints similar,the following very gradually decreasing ⁱⁿlength, those ⁱⁿthe terminal third of the cirrus beingaboutaslong^asbroad; antepenultimatejointaboutone-third longer than_l)road; penultimate joint half again ^as long ^asbroad, slightly ^less indiameter thanthe preceding; opposingspine very small,though promi- nent,terminallysituated,directed obliquelyforward; terminalclawabout as long ^as the penultimatejoint, stout basally,

becoming

^{slender inthe}

distal half, moderately^curved.

The

cirri aremoderately compressed ⁱⁿ the^distaltwo-thirds; thetwoorthree_joints before thepenultimate have slight traces ofterminal dorsaltubercles.

Disk coveredwitlia j^avement^ofvery small plates; side

and

_covering

plates welldeveloped along^theambulacra.

Ends

ofthe basal rays^visible as large rhombic tubercles inthe angles of the calyx; ^radialsonly^{visible as} a _large transverselyoblong^tubercle between the centro-dorsal

and

the iBri; iBri very short, arcuate, ⁱⁿ close lateral apjiosition, the proximal edge

more

or less crenulate,

and

bearing alarge

and

rather high transversely oval

median

_tubercle; iBro (axillary) rhombic, veryshort,

somewhat

over twice as broad _{as long,} the edges

somewhat

crenulate

and somewhat

_produced, the proximal imbricating

more

orless over the anteriorborderoftlieiBri; thelateral edges are veryshort, in closeapposition; ^itbearsa rather_large

and

_high roiinded

median

tubercle; ⁱⁱ

Br

4(3 -1- 4) ⁱⁱⁱ close lateral apposition

and

sharply flattened, withthe lateral edges slightlyeverted; thedistaledge ofIIBriis

somewhat

_everted,

and

theproximal edge^ofii

Br2more

strongly everted, the ^latter imbricating slightly over the former except ^{in the}

median

line; ⁱⁱ

Bn

usually bears astrong rounded

median

tubercle like thaton thetwo

components

^{ofthe i}

Br

series.

Thirteen

arms

(inthe type)

170mm.

_{long,elongated}

and

comparatively slender, resembling^thoseofP. robu8ta.

The

_pinnulesingeneral resemble those ofP. robuala, butthe pinnules intheproximal part^ofthe

arm

are strongly^carinate.

Pachylometra

investigatoris sp. nov.

Tjipe.

—

_{Cat. No.}

_13A =

"*',;"" Indian

Museum; Malay

Archipelago, 30 fathoms.

Centro-dorsal a truncated cone, ⁷

mm.

broad at the base

and

5

mm.

high, the ^cirrussocketsarranged ⁱⁿ two columns of threetofiveeach ⁱⁿ each radial area, the

two

columns of each area separated by ^a

narrow

median

line not _quite so broad _basally as the cirrus sockets, distally narrowing

and

_ending ina point ^ataboutthelevel ofthe third or fourth

cirrussocket; the colmniis^of eacharea are_closelycrowded against,

and

tendtoalternatewitii,thecolumnsin adjacent^areas.

Cirri xi,, 2.5-28, about 40

mm.

long; ^tirstjointveryshort, second

and

third equal ⁱⁿsize, aliout twiceasbroad _{as long,} fourth _slightly longer, fifthaslong^asbroad; sixth,seventh

and

_eighthjointstlielongest,sliglitly longerthanl)road toaboutone-third again^aslong^asbroad,^tlie following very gradually decreasing ⁱⁿ length ^so that those in the distal half are about as long ^as broad, or, in

some

_{cases, slightly} broader than long;

third _joint from the

end

_{slightly longer} ^than broad; antepenultimate aboutone-third longer than _l)road; penultimate, whichis

somewhat

less indiameter thanthe preceding,^halfagain ^aslong^asbroad; distaldorsal edge ^{of the distal} joints showing an inclination to develop low ^blunt tubercles; opposing spine represented bya small blunt _tubercle, termi- nally^situated; terminal clawlong, al>out aslong^asthepenultimatejoint, moderatelyslender,

and

mo^lerately curved.

The

cirri arerounded_basally, but moderately compressed ^{in the distal} two-thirds; thereisnotrace of carination.

Disk completely covered

by

a i>avement^ofsmall_plates; side

and

cover- ing platesstronglydeveloped on ^thepinnule ambulacra.

Ends

ofthe basal raysvisible as largerhombictubercles intlieangles ^of the calyx^{; radials} concealed; iBri_short,four orfive times as broad as linig,chevron-shaped,^witha

more

orless

wavy

proximal

and

distalborder, in close lateral ap])Osition; theapposededges are

somewhat

thickened

and

produced

and

there area fewlow broad tubercles on thedistalborder;

IBra(axillary) rhombic,^twiceasbroad as long, rising to a rathersharp dorso-ventrally elongate tuberclewiththe ⁱBri; ⁱⁱ

Br

4 (8-F 4); onthree ofthe II

Br

seriesthe syzygy^isreplacedby^asynartbry^{; iii}

Br

2 (1

+

2), developed interiorly.

The

division series are very stronglyroundeddor- sally

and

have a _slightlyindicated

median

carination; they are ⁱⁿvery close lateral apposition

and

the lateral edges are slightlyi)roduced

and

evertedas in Glyptometra.

Thirty-two

arms

(inthe type) 150

mm.

long; ^firsttwoor four brachials oblong, short, united in syzygial pairs which are not quite ^so long ^as broad; following twoor three brachials oblong,

somewhat

over twice as l)r()adas long, then

becoming

wedge-shaped,^twiceasbroad _{as long,}

and

slightly longer

and more

_oblique after the proximal ^{third of the} arm, wherethe brachialshave_{slightly])rominent}distalends.

Pu

17

mm.

to20

mm.

long,very slender

and

flagellate distally,withfrom

fiftyto fifty-three joints: ^firsttwo_jointsilisproportionately large,twiceas liroad as long,stronglyflattened exteriorly; third_jointabouthalf asbroad asthefinst

and

half aslong^asthe second, twice^asbroadaslong^; follow- ingjoints tothefifteenthdecreasingⁱⁿdiameter

and

increasingⁱⁿlength, atfirsttwiceasbroad_{as long,}

becoming

^{afterthefifteenth}uniformly^small

and

about as long ^as broad; Pi about the

same

length with _forty-five joints, similar, but

much

less stout _basally

and

notta})ering so ra})i<lly;

V->l?i

mm.

_{long with} aboutthirty jointsaboutasstoutbasally^asthe pre- ceding pinnules, but _tapering

much more

gradually, the ^firsteightjoints aboutthree times asbroad _{as long,} then _gradually

becoming

longer

and

84

Clark

— _New

Recent Crinoids

from

^the

Indian Ocean.

squarish^alioutthe eighteenth

and

intheterminal part longerthanbroad;

P;j al)ont In

mm.

_long,

and

P4 16

mm.

^or17

mm.

long, reseml)ling P2;

Vr,similar, ^1:5

mm.

long; Pg similar

and

of the

same

_length; P7

and

the followingpinmiles ¹²

mm.

long^witli the_{joints in}theproximaltwo-thirds slightly

expanded

laterally; in the nextfourorfive the pinnules decrease in length^{to S} nun., while theexpansion^ofthejoints becomes

more

_pro- nounced, beginning on the second, reaching a

maximum

on the fourth or fifth, then _graduallydying

away

distally; distalj)iiinul('s stout as inthe other_{species of}the genus, 10

mm.

long.

Color (in _spirits).

—

_{Yellowishbrown.}

Family ANTEDONIDtE.

Genus

EUMETRA

A.H.Clark.

Eumetra

indica _sp. nov.

Type.

—

Cat. No. 4(t, Indian

Museum;

^PortBlair,

Andaman

Islands.

Centro-dorsal conical, 3

mm.

^broadat the base

and

3

mm.

high, the cirrus sockets arranged ^{in six} closely crowded alternating rows.

The

centro-dorsalasawholeresembles_closelythatofHathrometra.

Cirriabout_{i.xx, all lacking.}

Radialsextendingslightly

beyond

^theedge^ofthe centro-dorsal, diverg- ing^atan acute angle in the angles ^of the calyx; ⁱ

Bn somewhat

_trape-

zoidal, about three times as broad_{as long,} notin contact _basally; iBr2 (axillary)rhombic, ^thefree lateraledges rather longerthan those of the

IBri, forming^with

them somewhat more

than a_right angle; synarthrial tubercles moilerately developed.

Ten

arms, about⁶⁰

mm.

long; ^firstbrachial longeroutwardly than ^in- wardly,slightly incisedbythe second,notunitedinteriorly,butthe inner edges diverging ^atapproximately^aright angle; second l)rachial nearly twiceas large, irregularlyquadrate, with a rounded posterior })rojection incising thefirst; third

and

fourth brachials (syzygial pair)aboutaslong asbroad; nexteight or nine brachials slightlywedge-shaped, ^half again as broadas long, then

becoming

^almostor quitetriangular,aboutas long asbroad,

and

furtheroutonthe

arm

wedge-shaj^ed again

and

_longerthan broad. Syzygies occur between the third

and

_fourth, ninth

and

_tenth,

and

fourteenth

and

fifteenth brachials,

and

distally at intervals of three obli(piemusculararticulations.

Pi al)out 6

mm.

_long, very slender

and

_delicate,

somewhat

_stiftened, with about nine_joints, the firstaboutaslong as, or_slightlylonger than, broad, thesecond

and

third twiceaslong^asbroad, the following gradually increasingⁱⁿlength

and becoming

exceedingly elongateddistally^{; V-z}about 10

mm.

long, proportionately stouter than Pi

and

stifi'er, with fifteen joints, thefirstsquarish, thesecond_{slightlylonger}than broad, the third twiceaslong^asbroad, theremainderthreetofourtimesaslong^asbroad;

Pa8

mm.

long with^fifteen joints, similarto P2but_slightly less stout; P4 like Ps; P5 5

mm.

long, slightly

more

slender than _P4, with ten _joints, which haveslightlyeverted spinous ^distalends; following pinnules sim- ilar

; thedistal pinnules are lacking.

Color(inspirits).

—

Light brownishyellowwith traces ofabroad

median

dorsalline ofpurple.

Family FENTACRINITIDiE.

Genus

METACRINUS

P.H. Carpenter.

Metacrinus

batheri _sp. nov.

Type.

—Cat.

No. _-V!^, Indian JMnseum;

Malay

Archipelago; ¹⁶⁰

fathoni.s.

Stem

_stout, 7

mm.

indiameter, strongly ^{stellate in cro.ss} section, with the produced interradialanglesl)roadly roundedinsteadof sharp; ^cirrus sockets

conHned

tothe nodals, transversely oblong, the shorter diameter equal ^to the height ^of the nodals; nodals produced ^{at the} interradial angles intohighdorso-ventrally elongatetubercles,occupying their entire lateraledges; internodalssixor seven, alternatingⁱⁿ size,the longer^witii the angles produced into dorso-ventrally elongate ^tuliercles resembling those on the nodals, l)ut

somewhat

smaller; ^{radial faces} of internodals with low broad rounded _ridges, showing ^a tendency ^{to l)reak}

up

^into

tubercles, betweentheproducedinterradial angles.

Cirri45

mm.

to 50

mm.

long(about seven times tbe diameter of the stem) with forty -eight to _fifty joints, the lirst four veryshort, sube(]ual, the following increasing^totheninth which isnearly, or(piite, aslong ^as broad, then remaining ^{similar for five or}six joints

and

very gradually decreasing ⁱⁿ length distally, so that the later jointsareabouttwice as broad as long; ^cirriatfirsttransversely oval ^{in cross} section, gradually

becoming

^round

and

afterthefirstsixorsevenjoints laterallyGompressed;

on the terminal six or seven _joints there are indications of a

median

tubercle; terminalclaw as long ^asthetwo precedingjoints, conical, only .slightlycurved.

Basals veryprominent, ^shieldshaped,^{in lateral} apposition ^all aroimd the calyx, strongly produced

downward

over the angles ^of the stem _; radials narrow

and

_band-like, of equal height^allaround the calyx, four or five times as broadas long ⁱⁿthe

median

line; ⁱ

Br

4 (1-}-2); ii

Br

fiveto eleven (usuallyaboutseven);

arms

dividing four or^fivetimes, with usually one

more

_{axillaryexteriorly} than _interiorly in reference to the

II

Br

_series;

arms

as far astheiii

Br

axillary robust, the articular tuber- clesrather strongly indicated, the dorsal surfaceperfectly

smooth

;

beyond

the ^III

Br

_axillarythe brachialshave prominentfinelyspinous^distalends,

and

arerough ^{t(jthe touch.}

The

pinnules areessentially likethoseof 31. acutus.

Color_{(in spirits).}

—

_White.