Corvospongilla caunteri, nov.
Sponge forming thin films of considerable area not more than 3 or 4 mm. thick, of a bright green colour, moderately hard but friable. The surface smooth; oscula inconspicuous, surrounded by shallow and ill-defined radiating furrows; a very stout basal membrane present.
Skeleton reticulate but almost devoid of spongin, the reticulations close but formed mainly by single spicules; skeleton-fibres barely distinguishable. A close layer of spicules lying parallel to the basal membrane.
Fig. 48.—Corvospongilla caunteri (type, from Lucknow).
A=Gemmule; B=gemmule-spicules; C=flesh-spicules; D=Skeleton-spicules.
Spicules. Skeleton-spicules variable in size and shape, almost straight, as a rule smooth, moderately stout, blunt or abruptly pointed; sometimes roughened or spiny at the tips, often sharply pointed. Flesh-spicules minute, few in number, with smooth, slender shafts which are variable in length, never very strongly curved; the terminal spines relatively short, not strongly recurved. Gemmule-spicules amphistrongylous or amphioxous, irregularly spiny, slender, of variable length.
Gemmules free in the substance of the sponge, spherical or somewhat depressed, very variable in size but never large, having a thick external pneumatic coat in which the air-spaces are extremely small and, inside this coat, a single rather sparse layer of spicules lying parallel to the gemmule. A single depressed aperture present.
Habitat. Hazratganj, Lucknow; on piers of bridge in running water (J. Caunter, 29-30. iv. 11).