LIMNAINA. 87 
long as the aperture, whorls rounded; outer 
lip not spreading. 
Subgenus Lrunorysa, Fitzinger. 
L. reflexa, Say (L. umbrosa, Say), L. at- 
snuata, Say, L. Shurtlefii, Tryon, L. Hayden, 
ea, L. palustris, Miill., (L. fragilis, Hald.), 
» proxima, Lea, L. Rowellii, Tryon, L. 
raskii, Lea, L. desidiosa, Say, L. emarginata, 
ay, L. catascopium, Say, L. caperata, Say, L. 
srownit, Tryon, L. Gabbii, Tryon, L. Adeline, 
‘ryon, L. Vahlit, Beck, L. Holbollii, Beck, L. 
itrea, Hald., L. pallida, Adams, L. bulimoides, 
ea, L. arctica, Lea, L. Smithsoniana, Lea, L. 
dlida, Lea, L. humilis, Say, L. ferruginea. 
Lald., L. techella, Hald. 
Shell nearly cylindrical; spire thick, 
lengthened; aperture small, 
Subgenus LeprotimneA, Swainson. 
L. Kirilandiana, Lea, L. lanceata, Gould. 
. Shell very slender, spire attenuated, whorls 
flattened, oblique; aperture produced, ex- 
panded, without fold, 
Subgenus AcELLA, Hald. 
L. gracilis, Jay. 
(61) 
