Report on the zoological collections made in the Indo-Pacific Ocean ...

8P0NGI1DA. 423Hah. Port Darwin, 8-12 fms., bottom sand, mud, &c. ; ArafuraSea, 32-36 fms., bottom sand, mud, and shells ; Torres Straits.Several dry, more or less imperfect specimens, all somewhat overgrownby Polyzoa, Hydroids, or other Sponges ; and one in spirit,showing the only at all complete extremity. The largest measures155 millim. (6:j inches) in present length, and was probably quite250 millim. (12 inches) long when perfect. The species is an extremeform of the same elongate type as R, spathuJ-ifera, but does notbranch, and there is no indication in the present specimens offlattened extremities like those of that species ; the spicule is stouter,longer, and more approaching a cylindrical form than in that species.GELLIUS.Grm/, P. Z. S. 1867, p. 538.Asychis, id. I. c. p. 539.Desmacodes, Schmidt, Sponff. Atl. Geb. p. 54 ;Vosmaer, Notes Roy.3Ius. Netherl. ii. p. 101.Fibularia, Carter, Ann. ^ Ma;/. N. H. 1882, ix. p. 282.The identity of Schmidt's genus with Gray's might appear to bequestionable, as Schmidt, besides the acerate and bihamate spiculeson which Gray bases his definition, describes also a spinulate andcylindrical one (" Stift "); but I fail to find these forms on the slide ofthe type species which the Museum possesses from Prof. Schmidt.The genus, which maybe defined as "consisting of massive or erectforms, with loose brittle texture, and a skeleton smooth acerate, anda flesh bihamate spicule," is widely distributed ; the proportions ofthe sjncules vary little, and the external form has chiefly to be reliedupon in distinguishing the species. It is unfortunate that Dr. Gray'sgenus, which, like many others made by him, is suflSciently characterized,and is prior to names assigned to the genus by otherauthors, has not come into general use, since many synonyms havebeen thereby created. Sollas(Ann. & Mag. N. H. 1882, ix. p. 427)upholds Gray's genus Thenea against aU comers in a similar way,and is supported by Norman {apud Bowerbank, Monograph Brit.Sponges, iv. p. 29).Horny matter is not usually to be detected in the skeleton.58. Gellius conchi, Boiverbanlc, var. ceratina, nov.Halichondria couchi, Bowerbank, Man. Brit. Spang, iii. p. 203,pi. Ixxxi. fiiis. 12-15.Halichondria elegantia, id. P. Z. S. 1875, p. 286.As Vosmaer (I. c.) has suspected, the above two species are bothcongeneric with Desmacodes Jibulatus (Schmidt, sp.) aTid agree withit in having a spiculation composed of an acerate and bihamate.Bower1)imk's type specimen of //. couchi, which I have examined,contains plenty of the latter spicule ; and his own statement tothe contrary (P. Z. S. 1875, p. 286) is obviously an error, as hehimself describes and figures these spicules from this species (Mon.