f l
Terms emqiloyed.—These are essentially those used by Mr. Carter,
as in my Eeport on the ‘ Alert ’ collections from the South-American
coast (Proc. Zool. Soc. 1881). The measurements given for spicules
are the average maximum measurements; the diameter of a
spicule is its greatest diameter; sqmies are uot included in spicule-
measurements.
CERATOSA.
Ceraospongise, Schmidt, Sqmig. Adr. Aleer. and Atl. Geh.
SPONGllDHl.
Bibulida, and Hircinida, pars, Carter, Ann. Mag. N. H. (4) xvi.
p . 1 3 2 .
1. Cacospongia mollior.
Schmidt, Adr. Aleer. p. 27.
A specimen in spirit, pedicellate, consisting of one prominent lobe
and a lower broader portion, and a fragmentary skeleton. The apices
of the connli are about 2 millim. a p a rt; the consistence is firm hut
compressible and elastic, the dermis black and glabrous, the sarcode
rathcr opaque yellowish brown; the primary fibres long, straight,
and with very rare foreign bodies, diameter 1 millim. ; the secondaries
making very various angles with the primaries, and forming
numerous irregular meshes of variable size and angular shape;
diameter of fibre -035 to -07 millim.; fibre of both kinds coarsely
laminated.
The specimen is 68 millim. ( 2 | inches) high, 25 millim. in greatest
breadth, 12 millim. in greatest thickness, and seems to agree in the
main with Schmidt’s species, although the network of the fibre is
less regular and close.
Hah. Prince of Wales Channel, Torres Straits, 5 -7 fms.
Distribution. Adriatic (Schmidt).
2. Enspongia foliácea.
? Spongia foliácea, Dsqier, PJlanzenthiere, Fvrtsetz. i. p. 201, pi. Ivi.
? Platychalina foliácea, Ehlers, Die Espersch. Spong. p. 21.
I t is with much regret th a t I have to express a doubt whether
the sponge for which th at careful observer, Prof. Ehlers, established
the above genus is, as he asserts, a Chalinid. My reasons are as
follows :—Erom H.M.S. ‘ Alert ’ there has been obtained a sponge,
in fine preservation although dry, agreeing minutely with Esper’s
figure and description, except th at the “ pores ” arc smaller and more
scattered and numerous, and not placed on the back, but on the
front. With the exception of a very few fragments of spicules of
different thicknesses, found singly and rarely in a few fibres, there
are no spicules at all, and the sponge is evidently a Ceratose species,
differing from the common species of Euspongia only in its flattened
form. The fibres of the main skeleton agree in their consistency
and non-rectangular arrangement with those of Euspongia, and, as
stated already, foreign bodies are the exception even in the surface-
tufts ; the diameter of the fibres is -4 to -7 millim. (Ehlers gives -5
to -8), except in the delicate itZte/a-network of the surface and interstices,
where it is -0085 to -022 millim. Ehlers says th at the
fibres contain “ in der Axe vereinzelte sehr dünne spitz-spitze
Nadeln (OG mm. lang, -006 mm. breit) welche nur in den kegel-
foimigen Zuspitzungen an der Oberfitiche des Schwammes etwas
dichter gehäuft sind.” Their occurrence singly (“ vereinzelte”) and
not in longitudinal series, if th at is what is implied, is not the usual
mode of occurrence of spicules in the fibres of Chalinidæ (though it
occurs occasionally in some fibres of Cladochalinoe), nor is their
greater abundance in the surface-tufts, so far as I know, usual in
this family. These statements appear to me to point towards the
true explanation of the nature of these spicules, viz. th a t they are
foreign, and taken in (as is usually the case in Euspongia) as foreign
bodies in small quantities into the surlace-tufts. A re-examination
of the original specimen is desirable. I f Esper’s species is a Chalinid,
then the present species is a Euspongia-iaoraovgh of a Chalinid form]
like the Chaliuopsid representatives of Siphonocludina and Paeliycha-
hna which Schmidt (Spong. Meerbusen Mexico, p. 80) has described
as Siphonochalinopsis and Pacliyclialinopsis.
I have satisfied myself th at another explanation which might be
suggested, viz. the dissolution of the spicules from the fibre of the
Sponge (as in Carter’s Aplysina chalinoides, afterwards found to
be a true Chalinid), cannot apply to this case. I have studied
the fibre very carefully, with and without the aid of potash, and can
assert th at it never possessed “ proper ” spicules.
The respective localities (Cape and Torres Straits) perhaps constitute
relative objections to the specific identity of the present with
Esper’s species.
Hah. West Island, Torres Straits.
Distribution. Esper’s species is from the Cape of Good Hope.
3. Euspongia officinalis, Linné, var. cavernosa, (P la te XLI. fig. g.)
From a depth of 10 fathoms in Torres Straits we have a small
turnip-like sponge, unfortunately preserved only in the dry state,
which to the unaided eye presents the general appearance of a lih i-
zochalina fistulosa, with several tubular processes, 10 to 35 millim.
long and 8 to 10 millim. in greatest median diameter, on its upper
surface ; these processes are, however, ragged in outline at their
distal ends, and evidently in life opened through the fringed aperture,
now obscured by the falling together of the sides ; their sides are
in some cases fenestrate. The body of the sponge is rudely globular,
and is drawn up above into monticular elevations, which are terminated
by the tubes ju st described ; the base is somewhat fiattened,
and has apparently been attached at three points to rock or gravel at
the sea-bottom, portions of which are still left imbedded in the sponge.
The chief horizontal diameters of the sponge-body are 45 and 55
35 ijill
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