A new crinoid from New Zealand, and another from Tasmania

Vol. 31, pp. 41-44

May

16, 1918

PROCEEDINGS

OFTHE

BIOLOGICAL SOCIETY OF WASHINGTON

A NEW CRINOID FROM NEW ZEALAND, AND AN OTHER FROM TASMANIA.

BY AUSTIN H. CLARK.

[Published withthepermissionof theSecretaryoftheSmithsonianInstitution.]

The development

^of the crinoid

fauna

of the

waters about

New Zealand and Tasmania has been

singularly slow, ^{for it is}

not

_yet

seven

years since the ^first crinoid

was recorded from Tasmania, and only a

^little

over a year

^since

the

first

New

Zealand

_species

was

described.

At

present the following

forms

are

known from

these

two

localities:

New

Zealand.

Comanthus benhami A.

H.

Clark.

(Proc. Biol. Soc. Washington, ^vol. 29, Feb. 29, 1916, p. 48.₎ Comanthusnovsezealandise, sp.

no

v.

Argyrometra^mortenseniA.

H.

Clark.

(Jonrn.

Washington

^Acad. Sci., vol. 7, No._5,

March

4, 1917, p.129.) Tasmania.

Comanthustasmaniee, sp.

no

v.

(Comanthus trichoptera [part] A.

H.

_Clark,

Mem.

Austr. Mus., vol. 4, part 15, Aug. 17, 1911, p. 755.

—

Comanthusspanoschistum [part]

H.

L.

Clark, ^Biol. ResultsFishing Exper. ^F.I.S.Endeavour, 1909-14,

June

2, 1916, p. 17 [MariaIsland, Tasmania; BassStrait].)

<omanthusplectrophorum

H.

L.Clark.

(Biol. Results FishingExper.^F.I.S.Endeavour, 1909-14,

June

2,1916, p. 15 [BassStrait].)

Comissia spanoschistum (H. ^L. Clark).

(Comanthus spanoschistum [part] H. L. Clark, Biol. Results Fishing Exper. ^{F. I. S.}Endeavour, 1909-14, p. 17 [Maria Island,

Tasmania;

Bass _Strait].)

Austrometrathetidis (H. L. Clark).

(Biol. Besults Fishing Exper. ^{F. I.S.} Endeavour, 1909-14, p. 22 [Bass Strait].)

13—Proc. Biol.Soc.Wash.,Vol.31, 1918. (41)

42

Proceedingsof the Biological Society of

Washington.

Ptilometramacronema(J. Muller).

(H. ^L. Clark, Biol. ResultsFishingExper.^F.I.S.Endeavour, 1909-14, p. 23 [BassStrait].)

Cosmiometra dasybrachia

H.

L. Clark.

(Biol. ResultsFishing Exper. ^{F. I. S.} Endeavour, 1909-14, p. 24 [Bass Strait].)

Compsometra incommoda (Bell).

(H. L. Clark. Biol. Results FishingExper. ^F.I.S.Endeavour, 1909-14, p. 25 [Flinders Island].)

Metacrinus cyaneus

H.

L. Clark.

(Biol. ResultsFishing Exper. ^{F. I.S.} Endeavour, 1909-14, p. 9 [Bass Strait]^.)

Comanthus

tasrnaniae, sp. nov.

Description.

— The

centrodorsal isdiscoidal, rounded pentagonal ^inout-

line, extremely thin, 4

mm.

in diameter; the cirri are arranged ^{in a} singleincomplete

and more

orlessirregularmarginal ^row.

The

cirri are

XX,

14-16, slender, 10

mm.

_{long; the} ^first_segment is

broader than_long,thesecondisaslongas,or_slightlylonger than, broad, the third is twice as long ^as broad, the three followingabouttwo

and

one-half times as long ^as broad,

and

their successors rapidly

become

shortersothattheterminal eight are broader than long; these ^last are

somewhat

_compressed laterally

and

in lateralview appearslightlybroader thanthose preceding; with the one or

two

_preceding they each bear ^a small pointedsubterminaltubercle.

The arms

are 37in

number,

65

mm.

long, and resemble those of C.

trichoptera; the^distaledges^oftheossicles ofthe divisionseries

and

ofthe brachials (especiallythelatter) are strongly everted

and

_{finelyspinous.}

Habitat.

— _Tasmania;

Ihave

examined

two _specimens, one in thecol- lection oftheAustralian

Museum

atSydney, ^{the other in the collection} oftheU. S. National

Museum

(No.34976).

Remarks.

—

This_speciesprobably^{includes the} multibrachiateexamples listedunder ^Dr.

H.

L. Clark's

new

_species Comanthusspanoschistumfrom BassStrait

and

Tasmania.

The

ten

armed

_specimens, which Dr.Clark especially

had

in

mind when

he wrote the description, appear ^to belong not to Comanthus, but to Comissia, for the lower pinnules^asdescribed agreewiththoseof Comissia. Dr. Clarknotes the "absenceof the pecu- liar axillaries characteristic of" Comanthus trichoptera,

and

states that

"

many

^ofthe specimens,eventhesmall ones, havethe _genital pinnules

immensely

^swollenwith the reproductive cells."

Comanthus

novaezealandiae, sp. nov.

Description.

— The

centrodorsal is discoidal, irregularly circular in out- line, broad, ^flat

and

_{verythin, 5}

mm.

in diameter; the^cirriarearranged ina_singleirregular

and

_unequallydeveloped marginal^row.

The

cirri are

XIII+,

17, rather slender, 10

mm.

to 11

mm.

long;

the first segment ^is very short,the second twice as broad _{as long,} the

Clark

— _New

_{Crinoids from.}

_{Tasmania and New Zealand. 43}

third from one-quarter ^to one-third again^asbroad _{as long,} thefourth about halfagain ^aslong^as broad, the^fifthabout twiceaslong ^asbroad, and thesixth nearly^aslong; thefollowing rapidly decreaseⁱⁿ length so that ^tlielastseven arebroaderthan_long; these are

somewhat

_compressed

laterally

and

thereforebroaderin lateralview thanthe preceding^; fromthe fourth

onward

thedistaldorsal border is thickened,^this thickening be-

coming

graduallynarrower

and more

_prominentin the central portion ^so that onthelasttwo or three before the penultimate^{itresolves itselfinto} a low sharp subterminal tubercle; the opposing spine hasa transversely broadenedchisel likeedge.

There^{are 20}arms, ^inthe specimen^at

hand

^allbroken offat thebase.

The

distaledges^oftheossicles of the division series

and

of the brachials are veryslightlyprominent,

and

arebordered with_veryfine spines.

Habitat.

—

Three KingsIsland,

New

Zealand. Dredged

on

hard bottom in Gofathoms

by

^Dr. Th. Mortensen, January5, 1915.

Remark*.

—

Thisspecies differsfrom C. lasmaniae, towhichitappears ^to be

most

closely related, in having^fewerarms,inthe lesser length ^of the earlierelongated^cirrussegments,

and

inthe swollendistalbordersofthe earliercirrussegments, the^distalborderofthefirstsevencirrussegments in C. lasmaniaebeingquiteunmodified.

It is easily distinguished from C. benhami, from Preservation _Inlet,

New

Zealand,

by

^{the fewrer}arms,the

much

shorter _cirri,

and

the fewer cirrussegments.

As w

^re

know them

atthe presenttime thestatus oftheformsrelated to C. trichoptera ^is very ^uncertain.

Much ^more

material, _especially from

Tasmania and New

Zealand,^is neededto clear

up

^{thesituation.}