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

;622 COLLECTIONS FROM THE WESTERN INDIAN OCEAN.44. Suberites, sp.A dull red-brown, smooth, incrusting film, about '5 millim. thick ;the closelj'-set spiiiulate spicules measure about '8 by '02 millim.the head is distinct, suboval, approaching a globular form, andof about the same diameter as the shaft. No other spicule. Thespecies is perhaps nearly allied to S. autarcticiis, Carter.Hab, SeycheUe Islands, 12 fms.45. Vioa sclimidti.Vioa johnstoni, var., Schmidt, Sponcf. Atl. Oeh. p. 5,Vioa schmidti, Ridley, P. Z. S. 1881, p. 130.Vioa Schmidtii, Carter, Ann. Sf Mag. N. H. 1882, ix. p. 354.The specimen agrees with Schmidt's species from the Bocche diCattaro (Adriatic), which Mr. Carter and myself have agreed inconsidering distinct from the original V. jolinstoni from Sebenico.As the species has never been fully described, I give a descriptionof the present specimen.Main cavities formed by sponge botryoidal, wide. Colour of spongebright piuk to crimson. Vent- and pore-areas '5 to 1*5 millim. indiameter. Barcode pale pink, for the most part very difi"usely coloured,transparent. Spicules :—(1) Spinulate, smooth, straight or slightlycurved, tapering gradually to sharp point ; head large, oval, longitudinallyelongate, distinguished from shaft by distinct neck, thediameter of which is '006 millim. ; length of spicule "28 millim.,diameter of shaft '008 millim., of head (transverse) 'OOOS millim.(2) Spinispirular, stout, with 4-6 sharp bends ; spines sharp,arranged in regular uniserial spirals, 5 or 6 to a bend, length thesame as thickness of the shaft ; size of spicule "05 by '006 millim.(excluding spines). (3) Spinispirular, slender, with about 8-10gradual bends, 5 or 6 to a bend ; size of spicule -075 by '002 to -0042millim. (excluding spines). Spicule no. 1 is generally loosely scattered; no. 3 sometimes aggregated in dense masses.Hab. Eagle Island, Amirante group, 10 fms. (in base of lobateMadrepora).Distribution. Adriatic (Schmidt).The stout spinispirular appears to be normally confined to that sideof the sponge which is in contact with the matrix, the slender one tooccupy the internal sarcode ; but they also occur mixed. Althoughthe two kinds of spinispirular spicule approach each other somewhatnearly in the diameters of their adult forms, yet the longer spinesand the constantly inferior length and inferior number of bends,and the superior sharpness of the bends, in the stouter form sufficientlydistinguish it from the slender form. A further argumentagainst the possibility of the two forms being merely stages ofgrowth of one spicule is derived from the fact that the more slenderform (which, from the analogy of siliceous sponge-spicules generally,would on this hypothesis be the young form of the other) is actually