Neiu Fresh-Water Sponges 



21 



" Heteromeyenia pictovensis, n. sp. — Sponge light green, 

 even when dry, massive, encrusting ; texture very compact ; 

 spicules non-fasciculated, persistent ; surface mostly smooth. 

 — G-emmules very scarce, spherical crust thick. — Skeleton 

 spicules cylindrical, short, robust, rounded, or abruptly 

 terminated ; entirely spined, spines conical at the centre of 

 the spicule, elsewhere generally curving/onward, or towards 

 each extremity. Rounded terminations of spicules covered 

 with short spines, though frequently a single large spine 

 or acute termination is seen at one or both extremities. — 



r^% 





Heteromeyenia Pictovensis. 



A. — Skeleton spicule. 



B. — Long statoblast spicule. 



C. — Short statoblast spicule. 



Dermal spicules absent or undiscovered. — Birotulates of the 

 longer class surrounding the gemmules, rather numerous, 

 one half longer than the others ; shafts conspicuously fusi- 

 form or largest at the centre, where are frequently found 

 one or more long spines ; their rotules consist of three to 

 six irregularly placed rays, recurved at the extremities. 

 — Birotulates of the shorter class abundant and compactly 

 placed around the gemmule; shafts mostly smooth, though 

 sometimes bearing a single spine; irregularly cylindrical, 

 but rapidly widening to support the rotules, which are 



