86 LIMNAINA. 
Roman, while others, including the more re- 
cently described species, are in Italics : 
1. Shell sub-ovate, last whorl ventricose; 
aperture more than half the length of the 
shell, greatly expanded, 
Genus Limnza, Lam. 
L. ampla, Mighels, L. decollata, Mighels (= 
eatascopium, pars. Hald.), L. columella, Say, 
L. macrostoma, Say, L. casta, Lea. 
2. Shell spiral, oblong, translucent, horn-col- 
ored; spire acute, more or less produced, 
last whorl ventricose ; aperture large, wide, 
rounded in front; inner lip with an oblique 
fold; outer lip simple, 
Subgenus Auricuna, Klein. 
L. stagnalis, Linn. (= jugularis and ap- 
pressa, Say), L. lepida, Gould. 
3. Shell thick in texture, ovate, inflated; 
spire short, outer lip not expanded, 
Subgenus Buiimunea, Hald. 
L. megasoma, Say. 
4, Shell ovate-oblong; spire conic; about as 
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