genus edwardsiella from southern california.

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DESCRIPTION OF A NEW SPECIES OF ACTINIAN OF THE GENUS EDWARDSIELLA FROM SOUTHERN CALIFORNIA.

By

J.

Playfair McMurrich,

0/the University of Toronto, Canada.

The

only species belonging to the family Edwardsiidae hitherto describedfromthewest coastisthat from Unalaska which Torrey^{^} hasidentifiedwith the Edwardsiasipunculoides of Stimpson.

The

present form differs markedly from this and is sufficiently different from ^other

known members

of the familytowarrant its recognition as a distinct species, for which I propose the

name

EdwardsieUacalifornica. It

may

beidenticalwithaform from San Pedro mentioned, but not described nor named,

by

Torrey in the paperjust referred to.

EDWARDSIELLACALIFORNICA, newspecies.

Anaheim Bay

(Creek),Cahfornia:

Muddy

shore, about one mile inland, at or below low water, one example;

mud

flats and shore at,or below,lowtide, "Stingaree Hole,"sixexamples.

Type.—Csit.No.30716,U.S.N.M.

AH

the examples were completely contracted so that both the capitulum and tentacles were concealed.

The

scapus

was

covered

by

the

brown

furfuraceous epidermis, characteristic ofEdwardsians,

and was

grooved longitudinally

by

eight rather deep invections, marking off asimilar

number

of broad longitudinal ridges. These latter bore large

and

usually prominent nematocystcapsules, which were arrangedin a single

row

onthe distal partof the scapus, but

more proximaUy

werein

two

orthreecloselyadjacent rows,sothatit

seems proper to refer the species to the genus EdwardsieUa.

The

physa

was

largeand smooth;itlacked the epidermis presentonthe scapus,but

had numerous

minuteparticlesofsand adheringtoit.

Color.

—

In examples preserved in

formaUn

the scapus

was

of a dark chestnut-brown color, duetothe epidermis,

and

thephysa

was

clear

and

transparent.

Size.

—

^Heightof

column

incontractedexamples2.8 cm.;diameter of

column

0.4cm.;lengthofphysa about0.3cm.

•H.B. Torrey. Anemones(oftheHarrimanExpedition)withdiscussion of variation inMetridiiun.

Proc.WashingtonAcad.Sci.,vol.4,1902,p. 378.

ProceedingsU. S.National Museum,Vol.44-No.1967 551

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552 PROCEEDINGS OF THE NATIONAL MUSEUM.

Structure.

— A

^series^oftransversesectionsshowedthat the

number

of tentacles

was

16,andthattheywerearrangedinthetypical

manner

with reference to the perfect mesenteries, namely, one over each directivechamber, three over eachsulculolateralchamber,

and two

overeachofthe otherchambers. Italsopossesses thetypicalarrange-

ment

ofthe mesenteries, therebeingin additionto theeightprotoc- nemesapair ofrudimentarymesenteriesineach protocnemicsulculo- lateral

chamber

and a single one in each lateral and sulco-lateral chamber.

As

isusualintheEdwardsiidse theserudimentary mesenteries areconfinedtothe uppermostpartofthecolumn.

Fig.1.—Tbansveesesectionofa protocnemic mesentery of Edwardsiellacalifornica. mp, MUSCLEpennon;nc,mematocystcapsule;pm, parietal muscle.

The

muscle pennonsof theprotocnemeshaveaverycharacteristic pattern.

They

resemble thoseof E.pudica

{=E.

adenensisFaurot) in that the mesenteries join

them

almost at the middle of their breadth(fig. 1),acondition that evidentlyresultsfromthe excessive development of the lateral or basal lamella of the pennon, which seemstobeadirectcontinuationoftheaxialmesogloeaofthe

pennon

and,likeit, bears

numerous

lamellae, which,however, aresecondary branches. In E.pudica these arearranged bipinnatelyonthe basal lamella,butinthe presentspecies,wliilethe

more

proximalones are arrangedin apalisade-like

manner

on oneside of the basallamella,

more

distallythelatterbreaks

up

intoa

number

ofirregularlybranch- ingplates,so that thelateralportionofthe

pennon

has theappear-

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No.1967. A

XEW

SPECIES

OP ACTINIAX—McMURRICH. 553

ance of a rounded lobe. Throughout the portion of the pennon medial to the point of attachment of the mesentery, the lamellae, though branchingtoa greater orlessextent,haveapahsadearrange- ment, gradually diminishing in height, however, to a point about

midway

between the attachment of the mesentery and the medial edgeof thepennon, beyond whichpointthey again rapidly increase in height;thereis thus a

marked

separation between amedial

and

a

more

^lateralgroupof lamellae.

There are about 16 well developedlamellae in the medialset

and

about9 inthe

more

lateralone, while the basal lamella bearsabout 14 secondary ones, the total

number

being, therefore, about 39 or 40.

A

shght thickening of the

endoderm

over the medial edge of

pennon

is noticeable, butit is lesspronounced than in

many

other species.

The

parietalmuscles areverywelldeveloped, consisting of about 8

more

orlessbranched lamellaeoneither side of the

main

axis,their relativebreadths beingsuchastogivethecrosssection oftheentire musclea

more

orlesshemispherical orroundedconical outhne.