56 U.S. NATIONAL MUSEUM BULLETIN 272 



Corvospongilla bbhmii (Hilgendorf, 1883) 



Plate 4, figures 4-6 



Spongilla bohmii Hilgendorf, 1883, p. 87.— Potts, 1887, p. 205.— Weltner, 1895, 

 p. 114; 189Sb, p. 119. 



Corvospongilla bohmii Weltner, 1913, p. 475. — Annandale, 1914, p. 245. — Cunning- 

 ton, 1920, p. 587.— Gee, 1931e, p. 34; 1932c, p. 27.— Arndt, 1936, p. 16.— 

 Penney, 1960, p. 35. 



Corvospongilla bohmii var. elegans Topsent, 1932a, p. 580. — Arndt, 1936, p. 16. — 

 Penney, 1960, p. 36. 



Material. — Slides of type material from ZMB in N. Gist Gee's 

 collection. 



Description. — Sponge, according to Hilgendorf (1883), forming 

 thin crusts overgrowing Eunapius nitens; according to Weltner 

 (1898b) forming encrustations on Aetheria species; little information 

 available as to outer morphology. Skeleton apparently loosely defined. 

 Consistency recorded as fragile. 



Megascleres rather short, and not very thick, slightly curved or 

 almost straight amphistrongyla, often with inflated extremities, 

 and covered with a dense coat of tubercles or blunt spines arising from 

 a broad base; length range 120-150 p,, width range 11-14 p; occasion- 

 ally a number of amphioxea also present, covered with very minute 

 spines and ranging 80-100 p in length, 3.5-5 p in width. 



Microscleres relatively abimdant in outer symplasm of the sponge, 

 represented by microbirotulates mth a smooth to sparsely spiny 

 shaft w^hich is slightly curved, and terminally with 4 to rarely 5 

 strongly recurved hooks of somewhat greater length than in other 

 species of this genus; length of shaft varying from 24-39 p, diameter 

 of rotules 10-12 p. 



Gemmoscleres not present in material for this revision; recorded 

 as bluntly pointed amphioxea ranging to amphistrongyla, more or 

 less distinctly curved, and covered with short acute spines; length 

 range 40-55 p, width range 14-15 p. 



Gemmules not studied by the present authors; recorded as sub- 

 spherical, of medium diameter, and adhering to the substratum. 



Distribution. — Found only in three localities of equatorial Africa. 



Color in life. — Apparently not yet observed. 



Discussion. — Even though this species remains insufficiently 

 known, it can be distinguished at a glance from all congeners by the 

 longer and more deeply cleft prongs of the microscleres. The infra- 

 specific separation of C. b. elegans by Topsent (1932a) from C. bohmii 

 of Hilgendorf (1883) and Weltner (1898b) appears unwarranted, and 

 the smaller and somewhat more slender spicular components of the 

 "variety" can be explained by its limited growth area on shells of 

 Aetheria sp. Topsent (1932a) furthermore considered C. scabri- 



