The Shell-Collector’s Handbook. 51 
PISIDIUM NITIDUM, JENYNS. 
SHELL suborbicular, in the upper part rather swollen, in 
all the other parts compressed, thin, very shining, finely 
and regularly striated; anterior side rounded and some- 
what truncate; posterior side slightly produced and 
sloping abruptly downwards; lower margin rounded; 
umbones obtuse and subcentral with a few separate and 
deeper grooves surrounding them; ligament short, not 
visible from the exterior ; hinge and teeth as in P. fon- 
tinale; muscular impressions distinct. Animal whitish ; 
siphon short, funnel-shaped, with a plaited outer margin. 
Length of shell 3, inch ; width 3th less. 
Habitat.—Ponds and pools. 
v. splendens (Baudon! Mss. Mog.): Shell lemon- 
coloured. 
v. globosa (Adams): Shell spheroidal. 
PISIDIUM ROSEUM, SCHOLTZ. 
SHELL somewhat oblong or subrhombic, ventricose, thin, 
glossy, with deep and regular concentric strize, yellowish- 
white or pale-horn colour; anterior side sloping abruptly 
downwards and truncate; posterior side produced and 
rounded; lower border almost straight; umbones very 
excentric, obtuse, prominent; ligament nearly invisible ; 
cardinal and lateral teeth small; muscular impressions 
not well pronounced. Animal opaline white, orange- 
yellow or rose-colour in upper part; siphon subconic, 
long, truncated and without plaits. 
Habitat.—Ponds and pools. 
