)24 



On Two African Freshwater Sponges. 



S. cerehellata has been recorded from Central India. If 

 Dr. Annandale is riglit in regarding this species as a form 

 of S. lacustris, then the two commonest European species, 

 E.Jluviatilis and S. lacustris, have to be added to the list of 

 African freshwater sponges, of which twenty-one species are 

 now known. 



A description of the new variety of E. jluviatilis is given 

 below. 



Fig. 1. — Ephydatia Jluviatili&y var. capensis, on reed, nat. size. 



Fig. 2. — Gemmule. 



Fig. 3.— Oxea. 



Figs. 4, 5. — Smooth and spined tornotes. 



Figs. 6, 7. — Amphidisks. 



Fig. 8 — End view of same. 



Fig:. 9. — Oxea oi E.fluviatilis from Thames, London. 



Figs. 10, 11. — Amphidisk from Thames specimen, side and end view. 



Ephydatia fluviatilis , Linn., var. capensis, nov. 



Sponge encrusting ; colour, alive or in alcohol, of a medium 

 brown ; surface in part smooth and uniform, in part pitted 

 and finely hirsute. Oscules scattered, level with surface, 

 inconspicuous, about 1 to 1*5 mm. in diameter. Flagellated 

 chambers small, oval, 20 X 16 fi. 



Gemmules large, oval, "75 mm. in length by '54 mm. in 

 breadth, with funnel-shaped tube opening flush with the 



