REVISION OF FRESHWATER SPONGES OF SPONGILLIDAE 53 



C. zamhesiana (Kirkpatrick) and C victoriae Annandale are poorly 

 represented in the material for this study, the latter to such an extent 

 that comparative work was impossible. It is hoped that futiu'e studies 

 will be able to assess and demonstrate the relationship of these two 

 species to others of the genus discussed. 



Sponges of this genus are most closely related to all Stratospongilla 

 spp., as elevated in this paper to specific status, the main distinguishing 

 criterion being the presence or absence of free microbirotulates in the 

 sympiasm. It is therefore possible that future discoveries of such 

 typical microscleres in species hitherto included in Stratospongilla 

 may result in the transfer of such species to Corvospongilla. 



Corvospongilla loricata (Weltner, 1895) 



Spongilla loricata Weltiier, 1895, p. 138. 



Corvospongilla loricata Weltner, 1913, p. 476. — Annandale, 1913b, p. 237; 1914, 

 p. 245.— Stephens, 1919, p. 94.— Gee, 1931e, p. 42; 1932c, p. 27.— Arndt, 

 1936, p. 16.— Jewell, 1952, p. 453.— Penney, 1960, p. 37. 



Material. — One defective slide of type, obtained from ZMB by 

 N. Gist Gee. 



Description. — Sponge apparently not yet reliably known, rele- 

 vant data absent from literature available. 



Megascleres of two distinct series: (1) large, feebly curved, and 

 entirely smooth amphistrongyla, ranging 220-226 m in length and 

 about 20 fi in width; and (2) somewhat more slender amphistrongyla 

 with distinctly inflated extremities, usually finely granulated, rarely 

 entu'ely smooth, ranging 125-130 m in length, and about 7 n in width. 



Microscleres represented by microbirotulates with a smooth shaft 

 and terminally with a smaller number of recurved hooks of medium 

 size; average length 20-40 n, diameter of the rotules 4-12 n. 



Gemmoscleres slightly curved stout amphistrongyla, sparsely 

 covered with stout spines, and of greatly varying dimensions; length 

 range 34-75 n, width range 8-14 ju- 



Gemmules spherical and large, ranging 500-950 At in diameter; 

 pneumatic coat practically absent, without discernible air spaces; 

 gemmoscleres forming a tangential mosaic layer on gemmular mem- 

 brane; foramen produced into a short porus tube. 



Distribution. — Hitherto known only from one locality in Africa 

 (no particvdar type locality given), grov/ing on shells of Aetheria sp. 



Color in life. — Not yet observed. 



Discussion. — It is to be regretted that this rather ill-known 

 species has been chosen as type species of the genus, for its relation- 

 ship to its many congeners has yet to be demonstrated. Until addi- 

 tional data become available, C. loricata must remain a doubt- 

 ful species and the assessment of probable synonymy cannot be 

 contemplated. 



