60 U.S. NATIONAL MUSEUM BULLETIN 2 72 



gemmular aperture always tubular, tube short and cylindrical, in free 

 gemmules usually 2 micropyles present. 



Distribution. — Apparently restricted to India, ranging from Bom- 

 bay to the southernmost tip of the subcontinent. 



Color in life. — Not yet reliably recorded; dried sponge pale 

 green. 



DiscvBSioN.—Corvospongilla ultima is a slightly aberrant member 

 of the genus, closely related only to C. caunteri with which it forms a 

 distinct group. Its megascleres are invariably smooth amphioxea, 

 and gemmules are found adhering to the substratum, as well as free 

 in the inner symplasm. The extreme paucity of free microscleres in all 

 specimens recorded caused initial diflSculties in the assessment of its 

 generic position. 



Annandale (1912d) erected an additional "variety" of this species, 

 C. u. spinosa, chiefly on the differing surface of the two forms of 

 sponges. After comparing the type slides of both, their spicular com- 

 ponents are considered by the present authors fully identical and 

 their separation, even on an infraspecific level, as unwarranted. 



Corvospongilla caunteri Annandale, 1911 



Plate 4, figures 7-10 



Corvospongilla caunteri Annandale, 1911c, p. 243; 1912d, p. 384; 1918a, p. 213. — 

 Gee, 1931e, p. 35; 1932c, p. 27.— Penney, 19G0, p. 36. 



Material. — Slides of syntype (N. Gist Gee). 



Description. — Sponge, according to Annandale (1911c), forming 

 thin crusts of considerable dimensions; surface smooth. Skeleton 

 rather loosely defined, reticulate, but almost devoid of spongin; 

 basal membrane well developed and stout. Consistency of live sponge 

 moderately hard but brittle. 



Megascleres variable in size and shape, as a rule almost straight, 

 bluntly or abruptly pointed amphioxea, entirely smooth; occasionally 

 granulated or spiny at their extremities, often sharply pointed; 

 length range 190-220 n, width range 15-20 /x. 



Microscleres represented by microbirotulates with a smooth shaft, 

 which is never strongly curved, terminal spines relatively short, not 

 strongly incurved; length range 22-38 ii, diameter of rotules 4-9 /x. 



Gemmoscleres usually slightly curved amphistrongyla, rarely 

 blunt amphioxea, irregularly spiny, and of greatly varying lengths; 

 length range 30-68 n, mdth range 7-14 n. 



Gemmules not adhering to substratum but free in lower parts of 

 inner symplasm, spherical to somewhat depressed, variable in size; 

 average diameter 600 n; pneumatic coat rather thick, apparently 

 consisting of very minute air spaces; below this layer gemmoscleres ar- 



