ART. 12 HEXACTINELLID SPONGES — OKADA 63 The dermal swordlike hexcactin is somewhat larger than that in

the typical species but is smaller than those of the specimens

from

other stations.

The

length _{of the} hilt ray is 120^. to 160^.

The

blade ray is generally

more

than three times as long,

up

to 550,a.

Guard

rays are

somewhat

shorter than the hilt ray,

measuring

88/*

to 145)U, in length.

Specimens B

(1, 2,

and

₃₎ are beautifully _preserved. Measure-

ments and numbers

of transverse

and

longitudinal

beams

are given in Table 17.

Table ^17.

—

Measurements and numbers _of transverse and longitudinal beams _of 3 specimens (B, 1, 2, and 3) of Euplectella oweni

64 PKOCEEDINGS OF THE NATIONAL MUSEUM

^vol.81

dermal ^hilt rays.

Form

h is smaller than

form

«,

measuring

68ja to 80^ ⁱⁿ diameter.

The nmnber

of terminals in a perianth varies

from

9 to 12.

The marginal

teeth of the terminal plate are 3 or 4 in

number and seem

to occur frequently

among

the parenchymalia or subgastralia of the basal parts of the entire stock.

Oxyhexasters occur abundantl}^ both in the

subdermal and

sub- gastral layers, being

more numerous

within the

former

layer,

and

least

numerous

in the

middle

parts of the

parenchyme

layer.

Each

principal ray usually bears four or five, sometimes only two, diverg- ing terminals.

The

principals

and

terminals of the oxyhexaster of E.

oweni

are

somewhat

slenderer than in either E. hnperialis or E.

marshalli, but observation of the specimens,

which may

be referable to E.

oweni

in this collection,

shows

that the principals are fre-

quently thick or that they occasionally

have

small knoblike swellings.

In

general, the principals that are provided with four or five termi- nals

seem

thicker than those beset with only

two

or three terminals.

The lophocome

is probably absent.

The

thin

and

rather short diactins

do

not exist in the strands of the comitalia

which

are provided with four tubercles at the center.

The

oscularia consist

mainly

of the

common

diactins, with either

two

oppositely or four cruciately disposed central knobs. Frequentlj^^

they are intermingled with

many more

pentactins, tetractins,

and

stauractins. Generally speaking the diactins are

commonly

located near the edge of the oscular

membrane, and

the other

forms

stand outside or in

among them

in

mode

of occurrence.

The

state of the oscularia

mentioned

above nearly resembles that occurring in E.

marshaUi.

The

sieve plate

shows parenchymalia

consisting

mainly

of tetractins

and

diactins.

The

latter

seem

to occur

more

abundantly

among

the

parenchymalia

_{than do} the former. Frequently diactins,

which

^are provided with one to four short tubercles at the center, occur

among

the parenchymalia.

The

small

and

large gastral pentactins are thinly beset with small prickles near their distal ends. Paratangential rays

measure

100/x to 160/x long

and

^C/.t to ^8/jl thick near the center.

The

distal ray meas- ures 44(V ^{to 528ft in length. Besides these} pentactins, large tri- radiates

and

quadriradiates frequently occur.

These

^are also tuberculated at the ends of the rays.

The former

have a smooth, straight basal ray, ending in a small, distinctly tuberculated pro- tuberance,

measuring

about 715/x long

and

22/a thick at the center.

Paired rays are 45/i long, strongly diverging, slightly curved inward,

and

also tuberculated at the ends.

The

basalia

have

a very broad, miter-shaped anchorhead, measur- ing 72/x across

from

tip to tip of opposed teeth.

The

latter are

weakly

AKT. 12 HEXACTIISrELLID

SPONGES — ^OKADA 65

developed,

measuring

24ju, to 28/* in length,

and

are four, sometimes

six, in

number. They

differ

somewhat from

those of the other speci-

mens

in

having

a strongly

rounded apex

at the head; not pointed as a gothic arch as in the other specimens

from same

locality.

In

specimen B, 2, the diameter of the parietal pore is usually 1

mm ^and

^{seems not to exceed this size.}

The

parietal ledges are prominently developed, frequently

measuring

5

mm

in height, espe- cially those of the"oscular

margin

close to the outer

margin

of the sieve plate,

which approach

6

mm

^{in height.}

The

wall of the

body

is also thick, as in specimen B, 1,

measuring

4

mm

at the middle of the body,

and becoming

gradually thinner

toward

the

upper and

lower ends,

measuring

2.3

mm.

Splculatlon.

— The

^hexactin of the dermalia is not so large as that of specimen B, 1, usually

having

the blade ray 830/a to 1,370|U, long.

The

jjaratangential rays are proportionalh'' very short,

measuring

66/A to 121/j, in length.

Form

5 of the floricome in specimen B, 1, is probably not present in this specimen.

The

basalia

do

not differ

from

those of the type specimens, except in being slightly robuster

and

in

having

a per- ceptibh' thicker shaft.

The

anchor teeth, of

which

there are five to eight in each

head

(usually six or seven) are strong

and

about ^CO/i long.

The

distance

from

tip to tip of

any two

oppositely situated anchor teeth is 80/x to 88fi.

The

shaft is 24ju, thick close to its origin

from

the head.

Specimen

B, 3, is the smallest sjDecimen obtained

from

the

same

lo- cation. It does not

have

such

prominent

parietal ledges as specimens B, 1

and

2.

They measure

2 to 3

mm

in height,

and

have sharp edges.

Sijnculation.

— ^Among

^{the basalia, there is} occasionally

found

a

much

smaller

form

of anchor-toothed spicule than in the typical form.

The

apex of its head is rather pointed as in a Gothic arch.

The

anchor teeth vary in length

from

12/«, to 24/*,

and

their

numbers

are constantly 4.

The

distance

from

tip to tip of

any two

opposed anchor teeth is 32/i to 56/i.

The

shaft close to the

head

is 8/* to 12/x thick.

The

spines on the shaft are not so conspicuous as those of the typical

form and become more

degenerate in

number and

length.

Especially in the smallest one (basalia?), the spines are very short

and

are projected at

wide

intervals. These

forms seem

to be inter-

mediate

and

probably grade over into the

common

anchor-toothed basalia

and

the pentactin basalia of these ^varieties.

An

abnormality, like that occurring in the specimen

from

station 4948, ^is

shown by

three short tubercular spines projected sideways

118040—32 5

66 PROCEEDINGS OF THE NATIONAL MUSEUM

^vol.81

from

one of the anchor teeth near the apex of the

head and

another smaller protuberance near the end of a certain ^spine.

Specimen C

^is beautifully preserved,

and

^its sponge

body

is nearly straight, phalluslike,

and

quite similar to the outer configuration of various specimens obtained

from

the southern part of

Japan

(espe- cially to the specimen

photographed on

Plate 6, figure _1, of Ijima's Contribution I).

Parietal ledges are present but not so prominently developed.

They run

irregularly in places,

and may ^approach

¹

mm

^{in height.}

Their free edge is fairly even, frequently being either blunt or sharp.

The numbers

of

beams

^{are as} follows : Circular, 39 ^; longitudinal at

upper

end, 31; longitudinal at middle, _28; longitudinal at lower end, 23.

Spimdation.

— ^The

^{oxea of} the oscular

margin

are prominent, being usually slightly curved compass-needlelike spicules with

two

very

weak

oppositely placed tubercles at their center

and

sharply pointed at both ends.

They

occur in tufts or projecting singly

from

the der-

mal

surface of the oscular

margin and

with the inner one-third to one-fourth of their length

embedded

in the oscular margin.

They measure

about 715/x to 780^ long

and

8/t thick at their center.

The

oxyhexaster is represented in greater numbers, as

compared

with the other specimens. It is especially

abundant

in the paren-

chyme,

differing

from

the specimens

from

Station 4878,

which have

fewer oxyhexasters

among

the parencyhmalia than in the subder- malia

and

subgastralia.

The same

abnormality of the basalia occur- ring in the specimen

from

Station 4878 is also

found

in this specimen.

Family ROSSELLIDAE

(F. E. Schulze) Ijima,

1903 Subfamily ROSSELLINAE

F. E. Schulze,

1897

Genus

CRATEROMORPHA

^J. E. Gray, 1872

CRATEROMORPHA

MEYERI RUGOSA Ijima

Crateromorpha

meyeH

var. rugosa Ijima, Annot. Zool. Japon., vol. 2, p. 49, 1898.

Crateromorpha mcyeri rugosa Ijima, Joiirn. Coll. Sci. Imp. Univ. Tokyo,

vol. 18, art. _7, pp. 71-74, pi. 4, figs. 10, 11, pi. 5, figs. 14, 15, 1904.

Two

large specimens of C.

m.

rugosa

were

trawled

up from

a depth of 103

fathoms

off

Kagoshima Gulf

(Station 4936).

Both

are badly macerated. One, a large fragment, is probably all the

body

proper of a large sponge,

and

the other is a nearly complete colony with a distinct large stalk,

which

during preservation

was

broken from

the body.

The

stalk

expands somewhat

abruptly