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

BPO'GIIDA. 395more in the secondary fibres) than is the case with the mountingwhich the Museum possesses from Prof. Schmidt. The spicules arechietly acerate, tapering gradually to sliarp points, characters whichI have already described iu those of Schmidt's specimen (P. Z, S.1881, p. 114); but here I find also a considerable number ofcylindricals, in some places with well-rounded extremities ; the sizeof both kinds is "OS by -0025 millim., which is almost exactly thesize I gave for those of Schmidt's slide (I. c. p. 114). On re-examinationof the latter, I find a few of the cylindricals present therealso, and the position of the spicules in the fibre is normally axialon the whole, and not superficial only, as I stated in the paper referredto : I was misled as to these points by the scantiness and badly preservedcondition of the small mounting which represents the species.Thus, with the exception of the more strongly spicular characterof the fibre, the present specimens do not difter essentially fromWest Indian specimens of the species. The diameter of the stem variesfrom 5 to 9 millim. (exclusive of the spines), and the spines are strong,viz. 2 to 3 millim. high. Vents at intervals of 6 to 12 millim.along the stem.Hah. Thursday and Alert Islands, Torres Straits, 3-7 fms. ; PortDenison, Queensland, 4 fms.Distribidion. Caribbean Sea (Dach. 4' J-^^'/i.) ; Florida, 9 fms.(Schmidt).It is interesting to have such a well authenticated case of identityof a "West-Indian and an Australian sponge.23. Cladochalina, sp.A spirit-specimen, of sub-erect habit, with stout amber-yellowhorny fibre and fusiform acerates, uni- or biserial, measuring '28 by•OIG millim. Stem subcylindrical, about 12 millim. thick, withoutsurface aculeations. I prefer to await more perfect specimens ratherthan risk an incorrect determination and description.Hab. Prince of "Wales Channel, Torres Straits, 5-7 fms. ; bottomsand and shells.24. Cladochalina nuda. (Plate XLI. fig. /.)Decumbent. Stems solid, slender, tortuous (branches? ; none occurin the specimens), irregularly cylindrical, more or less compressedfrom above in places, especially at points at which large vents occur;generally buUately swollen out laterally at the same points ; diameterirregular, 2 to 7, or 5 to 9 millim. in diflerent specimens. Surfaceeven, minutely rough to the touch, with occasional low pointed projections.Vents uniscrial, approximately confined to upper surface,6 to 12 millim. apart, circular, opening level with the surface, oroccasionally with edges drawn up, 1 to 3 millim. in diameter, 1 to3 millim. deep; walls cavernous, perforated by numerous excretorvcanal-openings. Texture in spirit compressible, but resistent, vervelastic ; outer wall parchment-like, tough ; colour pale umber-browii.