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

;8P0NGIIDA.4G9lufcernal structure rendered cavernous by the wide canals of theexcretory system ; texture of internal structures moderately tough,luternal skeleton formed of trabeculas and sheet-like expansionssome larger trabecular formed of crossed skeleton-spicules strengthenedby dense sarcode proceed from the interior and support thecortex ; they are from --1 to -S millim. in diameter. A strong cortex,about -8 millim. thick, tough, formed chiefly by the skeleton-spiculesmuch intercrossed, and united by a somewhat dense, brownish, subtransparentsarcode (becoming less visible when the specimen isdried). Spicules:— (1) Skeleton spinulate, strong, slightly curved ;head oblong, almost oval ; shaft gradually diminishing to about twothirds of its full diameter towards head, and tapering gradually tosharp distal point ; average maximum size -6 by "02 millim. (2)Spiuispirular, delicate, composed of about three rather sharp bends,with about 4 to 8 rather blunt spines, -0021 millim. long, to eachbend ; shaft of equal diameter in all parts ; average maximum size•032 by -0016 millim. (exclusive of spines).Hnb. Thursday and West Islands, Torres Straits, 4-7 fms.bottom sand or coral.Distribution. Trincomalee (Carter); Galle coast, Ceylon (coll.Dr. Oiidaatje).Mus. Brit., ex coll.The external appearance of this fine species is more characteristicand constant than is usual in the Suberitidae. Mr. Carter hasshortly described it, but without name. The largest specimenknown to me is one brought by Dr. Ondaatje, Colonial Surgeon,from Ceylon, which measures 225 millim. by 13(J millim. (9 by 5inches), by GO millim. (2| inches) in greatest thickness ; it wasobtained at or near low-water mark.The species is nearly allied to Hymeniacidon angulata of Bowerbank(Madeira), but has a skeleton-spicule of twice the diameter ofthe spinulate found in that species.The spicules show no striking variation in size ; the length of thespinulate varies from -55 to '63 millim. in different specimens ; itsbreadth and the size of the flesh-spicule are almost constant.Colour. This is produced by a number of globular or suboval cellsof olive-green colour throughout, provided with a large nucleus of adarker colour ; they measure about -0095 millim. in diameter, andhave a well-defined outline ; they appear to be confined to thomesoderm.99. Spirastrella congenera. (Plate XLIII. figs, d, d'.)Massive, attached by broad base, tending to rise into pyramidal orcylindrical lobes, each terminated by the vent. General surfaceeven, smooth (in dry state). Colour (in dry state) pale fawn. Vent(in the single dry specimen) oval, 8 millim. in greatest diameter,leading deeply into the body of the sponge, the margin level withthe general surface (in the single specimen a tongue-like process,8 millim. high, stands at one side of it). Internal structure cavernous,with wide spaces ; texture of internal structures moderately touo'h.