PROCEEDINGS

OFTHE

BIOLOGICAL SOCIETY OF WASHINGTON

NEW RECENT INDIAN CRINOIDS.

BY AUSTIN HOBART CLARK.*

A second

collection of recent crinoids received for

study from

the

Indian Mnsenm,

consisting

mostly

^of

specimens taken

ⁱⁿ

deep

water, includes

a

rather large

number

of

exceedingly

interesting

new forms,

^of

which

it

appears

^{advisable to}

publish preliminary

diagnoses.

Among

^the

manj^ important

discoveries

n)ade by ^the

Investigator,

none

^is

more

_gratifying

than

the find-

ing

^of

Bathyrrinus

^{in the}

Indian Ocean;

^{of the}

two forms

obtained, one, the largestrecent species

belonging

^tothe

family

Bourgueticrinidse yet

known,

^{is related to}

^a

species previously

dredged only

^{in the far eastern} tropical Pacific,

while the other resembles most

_closely the

remarkable form from

the eastern Atlantic described

by

Professor Perrier as Ilyocrinns recuperatus,

a

_speciesso peculiar that

he was

inclined toregard ^itas a _possi- ble

monstrosity;

^{these are}

both

so similar to the

aberrant

Apiocrinus recubariensis of

Crema

(referred

by ^{Dr. Bather}

^to

Millericrinus) as to suggest that that species

should

best

be

referred to Bafhj/crinus.

The

_species

_diagnosed

herein will

be

_fully described

and

figured ⁱⁿ

one

of the series of

monographs published by

the

Indian Museum dealing with

^the

fauna

of the

Indian Ocean.

Family C(3MASTERID^.

OenisCOI^rATrLA Lamarck.

Comatula

micraster _sp. nov.

Type.—

^{Cat. No.Z. E. V.} U-^, Indian

Museum; Andaman

I^ilands; 60 fathoms.

Centro-dorsal rounded-pentagonal, ^flush with, or very sHghtly ^raised above, the dorsal surface^ofthe_radials, withoutcirri.

•Publishedwiththepermissionofthe Superintendentof theIndianMuseum,Cal- cutta; cf.antea, pp. 75-86; also Proc.U.S.Nat. Mus.,^Vol.xxxvi,pp. 033-651.

22—Pkoc.Biol. Soc.Wash..Vol.XXII,1909. (143)

144

Clark

— _-New

_Recent

_Indian

_Crinoids.

Radialsshort, trapezoidal,four orfivetimesasbroadaslong;ⁱBri

and

2united

by

syzygy, thesyzygial pairbeing^al)!)uttwiceasbroad as long;

I

Bn

almost_entirelyor quite unitedlaterally^{; i}Br2free laterally.

Ten arms

50

mm.

to65

mm.

long,resembling, withthe pinnules, those of C._pectinala.

Gentjs

eOMASTER

L. Agassiz.*

Comaster _parvus

_sp. nov.

Type.

—

Cat. No. Z. E. V.

^^,

^Indian

Museum; Andaman

Islands;

53 fathoms.

Cirri xiii-xvin, 10-11, 8

mm.

_{long, arranged} in a _single or _partially double row

on

arather thickdiscoidal centro-d((rsal.

Ends

of the basal rays^{visible as} prominent ^{tubercles in} the angles ^of the calyx^{; radials}projectingslightlyl)eyond theedge^ofthe centro-dorsal; I Bri very short

and

band-like,just incontact liasally but widely diverg- ing^sotiiattheir lateral edges are separated by^{a Ijroad shallow}U-shaped gap; ^{I Brn} (axillary) triangular, twice as broad as long, the anterior angle very ^{acute; ii}

Br

4 (8 -1- 4), widely separated; in

Br

2 (1 -f- 2);

IV

Br

2 (1 -f 2), developed interiorly in reference tothe ii

Br

series, bnt seldom_present.

Forty

arms

60

mm.

to 70

mm.

long resembling, with the pinnules, thoseoftheother smallspecies ofthe genus.

Mouth

central or sub-central; anal tube small, sub-central ormarginal;

disknaked.

Family HF\IER0METRID/E.

Mariametra

_{gen. nov.}

Genotype.

—

Himerotnetra subcarinataA.

H.

Clark, ^1908.

The

formwhich¹described under the

name

of

Himerometra

subcari- natadiffersmarkedly from^{all theother}sjieciesinthegenus Dichrometra, where ^I

had

tentativelyjjlaced it,in having ^{a delicate}

narrow

carinate line inthemiddleoftliedorsal surfaceofthedivision series

and

firsttwo brachials, andiuhaving ^{the sides of the division series} thickly covered with finegranulationsforminga triangularfigure ineachinterradial area, witii theapex^ataboutthelevel of thelastaxillary, something^{similar to} the ornamentation found in certain species of Crinometra. There are also ditt'erences in_tlie,cirri

and

in the pinnules, and the surface of the disk adjacent ^tothe anil)ulacraisstronglyi)lated. It did not seem wise

' tocreate agenusfor this singleaberrant species, as ^it was then _im])ossi-

V)letojudge^ofthevalueofthecharacters exhibited, they not being

met

with inany^otherspecies of the HimerometridtT".

The

Indiancollection, however, ^contains another _species possessing the

same

general features which scjiarate Kulirarinata. from the remaining species of Dlchro)iietra, tliougli (liU'ering widely ^{in its} details,

and

^I have

now no

hesitation in creating ^a genus ^{for these} two peculiar forms,

which

I propose ^{to call} Mariametra.

*

('f.'iiiira,p. ST.

Mariametra

margaritifera sp. nov.

Type.—

^{Cat. No. 57B., Indian}

Museum; ^two

^{miles ofl' Great}

^West

TorresIslands.

Centro-dorsal rather small, ^discoidal.

Cirri xxi, 30-34, ¹⁵

mm.

long, the outer_joints with long dorsalspines.

Diskthickly covered withsmall calcareousplatesalong ^the ambulacra

and

onthe anal tube, with scatteringplates intheinterambulacral areas;

no

_platingafterthe lastaxillary.

Kadialsshort,about sixtimes as broad as long, gently convex _proxi- mally

and

correspondingly concave _distally; i Bri short, oblong, some-

what

over four times^asbroad as long, in lateral apposition

and

_slightly

flattened; ⁱ Brs(axillary) short, almost_{or quite}triangular,two

and

one- halfor three timesasbroadas long, in appositionlaterally; ⁱⁱ

Br

2; radi- alsand_portionofcentro-dorsalabovetheproximal

row

of cirrus sockets evenly

and

thickly covered with high small tubercles resend)lingthose on the dorsal pole ^of the centro-dorsal, ^this tubercular modification of the dorsal surface of the _joints extending distally in the interradial angles, occupying ^{tlie lateral third of the i}

Bn and

the ⁱ Br^

and

of theii

Br

series, thence diminishing ⁱⁿ width

and

disappearing on tlie second brachial; inner edges ^of the ii

Br

series similarly modified; ⁱ

Br

series with a

narrow and

low, but prominent,tubercular keel or

row

of tuber- cles;this is

much

less

marked

or altogether absent

on

^theii

Br

series

and

first

two

brachials, though sometimes ^{traceable to the lowest of the tri-} angular^{brachials; I}

Brand

^ir

Br

series

and

proximal oblong ^brachials with prominently ^{everted dentate} proximal

and

distal edges; ^as the brachials

become

wedge-shaped

and

triangular, the everted dentate ends

become

_gradually lower, transforming ^{into a rather} prominent finely spinous overlap

which

slowly^dies

away

distally.

Eighteen

arms

(in the type) apparently ³⁰

mm.

to 35

mm.

long, the proportions ^of the brachials being approximately^{as in}

M.

subcarinata.

Pi 4nmi. _long, moderately stout basally, but tapering rather rapidly intheproximal^half

and

slender_distally,with twelvejoints,thefirstthree squarish, the following increasing ⁱⁿ length

and becoming

^{about three} timesaslong ^asbroad_distally; P2 6

mm.

long, slender, but stouter than Pi and

somewhat

_stiflened, with about sixteen joints, at ^firstsquarish, but

becoming

^{three orfourtimesas}long^asbroad_distally; P3 similar to P2

and

aboutthe

same

size; following pinnules ³

mm.

_long, small

and weak

; distalpinnulesdelicate, 5

mm.

long.

Family COLOBOMETRID.E.

Genus

CENOMETRA

A.H.Clark.

Cenometra herdmani

_sp. nov.

Antedonbella (notof Hartlaul)) 1904.

Cuadwick,

ⁱⁿ

Herdman,

Report Ceylon Pearl OysterFisheries, Suppl. Rep. ^xi, p. 155.

Type.—

^{Cat. No.}

H—

^jIndian

Museum; Ganjam

^Coast,

Bay

^ofBengal;

12fathoms.

This_speciesresembles C. unicornis ingeneral appearance, butis

more

146

Clark

— _New

_Recent

_Indian

_Crinoids.

slender, especiallythecirri. It

may

^{atonce be}distinguishedfrom allthe other _species of the genus by^tlie paired dorsal tubercles on the cirrus jointswhicharesmall

and

situated very^closetogether; and _{l)y tiie}short- ness

and

comparative slenderness _{of P2,} which isvery ^slightly,

when

at all, longer than Pi; P2also has comparatively fewjoints, these

number-

ing^lessthan _twenty.

Cenometra

insueta _sp. nov.

Type.

—

Cat. No. 23H., Indian

Museum

;

Arrakan

_coast,

Burma.

With

the

arm

and ])inmde structure ^of the preceding,

and

the

same

slendernessof build, thisform has the paired dorsal tubercles^ofthecirrus jointssituatedwith theirapices

much

further_apart,abouttwo-thirds the transverse diameter of the joint facesinstead of lessthanone-halfas in C. herdmani.

GenusCYLL0METR.\ ^A.H.Clark.

Cyllometra

^soluta sp.nov.

Type.

—

Incollection ofIndian IMuseum; Straits of

Ormnz,

^atentrance

toPersian Gulf; ^-lS-49fathoms.

This _species in its general appearance ^{resembles C.}

manca

from the Philippine^Islands.

Centro-dorsalthin-discoidal,the bare polar area²

mm.

indiameter.

Cirri xvi, 21-28, ¹¹

mm.

to 13

mm.

_long,tlie fourth orfifthand follow- ingjointssubequal, aboutaslong^asbroad; thirdorfourth

and

following jointswithproduced ^distal ends, which soon transform into prominent paired dorsalspines,

becoming

single

median

dorsal spineson the termi- nalfive orsix.

Ray and arm

^{structureas in C.}

mnnca and

C. albopurp-nrra.

Fourteento sixteen

arms

55

mm.

_long.

Paabsent; Pi small

and

_very slender, 3

mm.

_long, with about twelve joints^; Pa the_largest

and

longestonthearm, ¹¹

mm.

_longwithseventeen joints, ^tliefirst notsolong^asbroad, the third twice^aslong^asbroad, the reniaiiiileralxmtthreetimesaslong^asbroad; the pinnule^is

much more

slenderthan thecorresponding pinnule^{in the other}species of the genus,

and

isnearlysmooth, thedistal edges ^of the _{joints in}the terminal por- tion projectingonly veryslightly; Pa 7nun. _long, similar to P2but_very slender, the _{joints distally} i)rojiortionate]y

somewhat

_longer; following pinnules

more

slendiT _still,about 5

mm.

_{long with} fifteen joints,

and

flexible, gradually decreasingⁱⁿ length^to4

mm. and

increasing again^to 8

mm.

distally.

Family TROPIOMETRIDJ]:.

Genus

ASTEROMKTHA

A.H.Clark.

Asterometra

mirifica _sp. nov.

Antedua lonyicirra (part) (not^of Carpenter) ^1803. Bei.i., Journ. Linii.

Soc. (Zool.)vol. 24, p. 339.

Type.—

^{Cat. No. **}

V,

^Indian

Museum;

Sahul Bank, ^{in 10°30^}S. lat., 125° E. long.

While

ingeneral similar^toAsteromelra longicirra, this species

may

^be

atoncedistinguished l)ythe presence^ofahighsharp

median

keel

on

the

I

Br

series

and

onthetirsttwobrachials.

Asterometra

acerba _sp. nov.

Antedon _longicirra (part) (not ^of Carpenter) ^1893. Belt,, Jonrn. Linn.

Hoc. (Zool.), vol. 24, p. ^3.",9.

Type.—CAt. No.

*V-,

^Indian

Museum;

Sahul Bank, ^{in 10° 30^}S. lat., 125° E._long.; collected by Capt. ^F. Worsley^{of the cable S. S.} Sherard Osbnrn.

In general this species comes nearest to.1. nnihusofthe Eastern Sea, butitisa

more

slender_species

and

_possessesten

arms

_only.

Cirrixx, 84-90, 55

mm.

_long,

more

slenderthanthose ofA. anthus.

Radialswith a moderatelyprominent dorso-ventrally elongate

median

tubercle; ⁱ

Br

series withafaintnarrow low

median

carination.

Ten arms

80

mm.

_{long, slightlj^}

more

slenderthan thoseof A._anthns, with _slightly longer brachials;

arms

_{strongly compressed distally} as in that_species,buttheoverlappingspines developed onthe brachials arenot nearly^solong or^stout.

Pinnules

much

_longerthanthose of.1. nuthns,

and more

_slender, with proportionately longer joints, those in the terminal portion being three times as long ^asbroad oreven _longerwhereas in.4. anthus _theydo not exceed twice the length: Pi^is7

mm.

long with twelvejoints; P2_similar, 7.5

mm.

long; P3slightlystouter8

mm.

long; Ps9

mm.

_long; distalpin- nules 13

mm.

long.

Family THALASSOMETRID.E

Sub-family THALA.SSOMETRIN.E.

GF.^aTS

CROTALOMETRA

A.H.Clark.

Crotalometra

sentifera sp. nov.

Tt/pe.-CAt. No. Z. E. \'. ^-^S Indian

Museum;

^10°

^{47M5'^}

^N. lat., 72° 40' 20'^E. _long.; 703fathoms.

This

new

form ismost_nearlyrelated toC. magnicirra

and

C. rustica_; whileof the

same arm

length or even

somewhat

_larger thanthe latter

(150 nun. to 1(30

mm. arm

_length) it is

more

_slender,the

arms

arefewer in

number

(twelveto sixteen),thecirriareshorter

and

lessstoutwithfewer joints (xx, 59-62, 50

mm.

_long),

and

the brachials after the proximal third ofthe

arm

bear long overlapjiing spineswhichare

more

orless flat- tened dorso-ventrally

and

rounded ortruncatedatthe _tip.

<;F.Nrs

TIIALASSOMETRA

A.II.flark.

Thalassometra

attenuata _sj).nov.

Type.—C&t. No. Z. E. V. ^'V'J-, Indian

Museum;

^22°

24^0"

N. _lat., 66°

bV W

^{E. long.;} 765 fathoms.

This very slenderspeciesappears ^toberelated to T. pergracilis, butis

much more

delicateeventhanthat_species.

148

Clark

— _New

_Recent

_Indian

_Crinoids.

Centro-dorsalconical, thesides slightlyconvex,⁸

mm.

broadatthebase

and

2

mm.

_{high, the}cirrussocketsarranged^{in ten}eolnmnsofnsnally

two

eacli, the_{pairs of}columns_{usuallyslightlyseparated radially} by^{a shallow} furrowor a coarsely tubercidar ridge.

Cirri xx, 62-71, elongated and _veryslender, 50

mm.

long, the longest jointsbeing^{twice as} long ^as broad, orslightly longer, those after about the twenty-lifth being slightlybroaderthan _lung; joints aftertheseven- teenth or twentiethwith the distal dorsal edge produced ^{into a serrate} ridge which soon gives place^to small carinate dorsal_spines.

Ends

ofthe basal rays^visiV)leassmall,thougliratherprominent,^tuber- cles in the angles^ofthe calyx ; radials just^visil)le or_entirely concealed, sometimes bearing on the dorsal surface a

row

ofsmalltullercles;

i

Rn

_very

short,widelychevron-shaped, ^the proximal andouter third ofthedistal edge

somewhat

everted

and

thedistallateralangles

more

orlessproduced^;

I Bra _(axillary) triangular, twice ^as broad as long, the anterior edges

somewhat

everted, the ^lateralangles

more

or less iJrodnced; ^ir

Br

⁴{?>

+

4),developedⁱⁿtwooutofsixspecimens, the ^lateraledges ^ofthe

compo-

nent_joints

more

orlessproduced.

Ten

tothirteen

arms

SO

mm.

to90nun.long,exceedingly ^{slendt^r,} hav- ing ⁱⁿgeneral

more

theappearance ^{of thoseof}

some

slenderantedonid thanofthoseofathalassometrid; firstbrachial_short,wedge-shaped,^twice as long exteriorly ^as interiorly, basally united interiorly, ^tlie anterior

and

_{posterior edges slightly}thickened, the ^lateral edges

somewhat

_pro- duced,

and

theantero-lateral angles, both interior

and

exterior,

more

or lessproduced ^; secondbrachial similarinsize

and

_shape; thirdandfourth brachials (syzygial pair) usuallyslightlylongerinteriorlythanexteriorly, half again ^as broad_as,to about as broad _{as, long;} next three or four brachials approximatelyoblong, twice ^as broad as long, then

becoming

triangular, ^as long ^as broad, distally slowly increasing ⁱⁿ length

and becoming

wedge-shaped, being twice^aslong^as broad in the outer part^of the

arm

; synarthrial tubercles ratherprominent^{; i}

Br

seriesand^lirsttwo brachials

smooth

dorsally or with^afew small low incons])icnous tul}ercles, usually withslightlyspinous ^lateral borders; followingi)racliialswith the dorsal surface studded _{with very} tine short _s])ines or sharp tubercles, which in

some

_specimens are nearly obsolete; ^at about the

end

of the proximal^fourthofthe

arm

the brachials beginto develoi)j^rominentlongi- tudinal striations which increase in fre(|uencyand _{heightdistally.}

The

proximal oblong^brachials havethe _pro.xinialand distalends

somewhat

prominent; ^afterabout the twentieth brachial the distal edgt's begin^to overlap,

and

inthe distalportion^ofthe

arm

the brachialshavetheilistal portion

somewhat

ex])anded, givingapproximately

thesame

^"dice-box"

appearancecharacteristic oftheterminal i)ortion ofthe

arms

intheAnte- donidfe.

The

_jiinnulesareessentially as inother_{species of}thegenus^; butthefirst three _i)inindeson each side ofthe

arm

nn' very strongly^carinate.

Subfamily

CHARITOMETRIN^.

Genus PAClIYLO:\rKTr;A A.H.Clark.

Pachylometra

^invenusta sp. nov.

Type.—

^Incollection ofIndianMnseuni; 11°

W W

^{N.lat.,93°16^ 00^'}

E. _long.; 569 fathoms.

This _species i.s in general similar ^to P. macilenta, bntdiffers in

many

details.

Cirri x.xiii, 20-2J, 30

mm.

to 34

mm.

long, rather slender as in P.

macilenta; the proportions ^of the _jointsare the

same

asinthat_species, butthedistal edges ^{of tlie}jointsare_slightly

more

thickened, giving the cirri asawholea

somewhat

_rougherajipearance.

Twelve

arms

(in the type) 170

mm.

long, slender, as in P. niacileuta:

thetwoII

Br

series are 4(3

+

4); theornamentationof thei

Br and

ii

Br

seriesisas inthat_species; i

Br

series, first

two

brachials exteriorly

and

first three interiorly, in close apposition

and

_shaqily flattened laterally, the apposededges

somewhat

everted; brachials with the

same

proportions^as inP. macilenta; buttheproximal sub-quadrangular ^brachials havethe distalends thickened

and

everted,andtheremainingl)racliialshaverather prominently overlapjiing ^distal edges.

The

distal intersyzygial interval

is four or fiveobliquemusculararticulations.

The

_pinnulesresemlile thoseof P. macilenta, ^Init the _genital 2>innules are

somewhat more

swollen thaninthat_species.

Family ANTEDONID.E.

GknusP-SiATHYROMETRAA.H.Clark.

Psathyrometra

gracillima sj). ik^v.

'&•^>

Type.-Cat. No._^-°i'-'^,Indian

Museum

; 19° 35'N. _lat.,92°24'E. _long.

272 fathoms.

This_speciesisevensmaller

and more

delicatethanP. mira, heretofore the smallest

known

species ofthe genus.

Centro-dorsal sharplyconical,4

mm.

broad at the base

and

2.5

mm.

high, separated ^{into five radial} areas _l>y five interradial furrows which are

somewhat

broaderthanthe adjacent^cirrus sockets; eight^toten well separated ^cirrus sockets in each radial area, arranged approximatelyⁱⁿ fourcolumns, though apparently

more

orlessirregular.

Cirri xi-i,, about25,35

mm.

long, slender,

smooth and

delicate.

The

ten

arms

which, except ^{for their} slenderness, resemble those of related species, areabout 100

mm.

_long.

Genxjs

TRICHOMETRA

a.H.Clark.

Trichometra

obscura sp. nov.

Type.—

^{Cat. No. Z. E.V.}

^V^,

^Indian

Museum;

^{7° 17'}

^30"

^N. lat., 76° 54'

00"

E. _long.; 430 fathoms.

Centro-dorsal_conical, thesides slightlyconvex,^3.50

mm.

broadktthe base and 3

mm.

_high.

Cirri lacking.

150

Clark

— _New

_Recent

_Indian

Crinoicls.

Radials even with the edge ^{of the} eentro-dor.--al; i Bri very short

and

band-Hke, not qnite ⁱⁿ contact _basally, the lateral edges diverging ^at a ratherbroad _angle; i Br2(axillary) almost triangular, slightly broader than _long, the anterior

and

lateralangles rather strongly produced, with a rounded _posteriorjirocess incising the ⁱ Bri.

The

ten

arms

resemblethose f)f the other_{species of} thegenus^{so far as} can be judged from^tliesingle mutilated specimen.

The

_longest

stump

measures9

mm.

tothe tenth brachial.

Family PENTACRINITID.E.

Gems

IIYPALOCRTNT'S A.II.Clark.

Hypalocrinus

^liliaceus sj). nov.

Type.—

^In collection ofIndianISInsenm; 10° 25^ 00'"N. _hit.,93°43' 00'' E._long.; 463fathoms.

Hypalocrinus ^{Ulaccns is}most nearly ^{related to}

H.

apringeri; the^inter- nodals are usually twelve^tofourteenin

number;

ⁱⁱ

Br

4 (3+4); ⁱⁿ

Br

_2;

theelementsofthedivision series

and

thelower brachials are not strongly everted as in

H.

s)>ringeri, but are rather prominentlyoverlapping,^this overlap forming ^{a rather} sliarp pointon theside of the brachial which bears the pinnule; ^thischaracter gradually ^dies

away

^after the jtroximal thirdofthe arm, disappearingalmo.st entirely inthe outerhalf.

The

first

syzygy^occursbetweenthesecondand thirdbrachialsas in Capillaster.

Family BOURGUETICRINIDiE.

Genus

BATHYCRINIS

WyvilleThomson.

Bathycrinus

woodmasoni

sp. nov.

Type.—

^{Cut. No.} V-Indian

Museum,

^{from (i°18'}lat., 90°40'E. _long.; 1,520fathoms.

This _speciesisnearest toi>. equalorialls from between the INIarquesas Islands

and

Central America, 2,320 fathoms, l)ut, though considerably larger, ^itisof a

more

delicate build.

Tlie _tyjic sjK'cimenconsists of astem lacking the topmost columnars.

Stem (without proximal portion⁾

smooth and

_{slender, enlarging very}

grailually towardtlu'root,thedistalcolumnars with thearticulationsnot e.-<peciailyswollen, ^tlu- radicularcirricoiilincd totheterminalcolumnar;

length 327

mm.,

^{witii one hundred six columnars.} Topuiost columnar ]>rcseut twice aslong ^as liroad, the following increasing^totwo and one-

iialf times as long ^as broad on tin- fourth,^tlien

more

_gradually to three timesaslong^as broad on the fourteentli,

and

_nearly four timesaslong asbroadonthe twenty-thirdamifollowing; length very slowly decreasing after above the _tiftieth, tlu' foiu-teenth from tiie distal end (root)

and

followingbeing^aslongaslu'oad ^;lastseven or eight with the articulations slightly swoIUmi; p(^rij)hery of the articular faces finely

marked

with radiating^lines except^atthe endsof the transverse ridge; proximal ^col-

umnars

_(piite cylindrical, the articulations

becoming

slightly enlarged afterthethirtieth;s(iuarishlower joints slightlyconstrictedcentrally as in those species of I'liizocrinus wiiich luive s(|uarish coluunuirs; radicular

cirri stout,but _{only the} bases preserved.

The

topmost columnars ^are

]

mm.

_longby0.5

mm.

indiameter; ^thoseinthemiddleofthestemare 4

mm.

_long

_by

¹

mm.

in diameter, while the squarish ones ^at thedistal end are 2

mm.

_long; the last seven or eight are ³

mm.

_long with oval ends thefaces of which measureo

mm.

by¹

mm.,

^{the two faces ofeach} columnar being approximately^atright angles^toeachother.

Bathycrinus paradoxus

sp. nov.

Type.

—

Cat.No. "V^, Indian

Museum; Bay

^ofBengal; 1,300 fathoms.

The

material consists of two broken specimens; one stem, apparently lackingmerely ^thetopmost^discoidalcolumnars,⁶⁷

mm.

inlength(thirty- eightcolumnars), broken ^{into five}parts; part^ofa_largerstem, including the root

and

twenty-one columnars,

and

a

crown

without the distal por- tion ofthe

arms

probably belonging ^tothelatter.

NearesttoB. recuperatus (Perrier).

Stem

_very slender; longest columnars of smaller stem 2.5

mm.

in length^; of largerstem3

mm.

;columnars ofmiddleoflargerstem^0.7

mm.

broadat the ends, ^{0.4 in}the middle.

Basals five, not anchylosed, forming ^{a basal} ring

which

_expands

slightlyanteriorly,

and

^is aboutaslong^as the breadth at the top ^of the stem; radialsforminga ringexpanding rather rapidlyoutward from ^the basals,thesidesevenly concave,

two and

one-halftimesasbroad_distally asproximally, ^half again ^as broad _distally as long^{; i} Bri trapezoidal, nearly twice ^aslong ^asbroad proximally; ^{i Br2}trapezoidal, nearly twice asbroad_{as long.}

Arms

_ten, all broken off nearthe_base,smooth, apparently ^{similar to} thoseofother_{species of}thegenus^;i

Br and

lower brachialswithabroad thin produced border; ^distal two-thirds of the ⁱ

Bn and

the following jointswith asharp

median

keel.