LIMN^IN^. 87 



long as the aperture, whorls rounded ; outer 



lip not spreading. 



Subgenus Limnophtsa, Fitzinger. 



L. reflexa, Say (L. umbrosa, Say), L. at- 

 tenuata. Say, L. Shurtleffii, Tryon, L. Haydeni, 

 Lea, L. palustris, Miill., (L. fragilis, Hald.), 

 L. proxima, Lea, L. Roicellii, Tryon, L. 

 TrasTcii, Lea, L. desidiosa. Say, L. emarginata, 

 Say, L. catascopium. Say, L. caperata. Say, L. 

 Brownii) Tryon, L. Qahhii, Tryon, L. Adelince, 

 Tryon, L. VaJdii, Beck, L. Holhollii, Beck, L. 

 vitrea, Hald., L. pallida, Adams, L. bulimoides. 

 Lea, L. arctica, Lea, L. Smitlisoniana, Lea, L. 

 solida. Lea, L. humilis. Say, L. ferruginea, 

 Hald., L. techella, Hald. 



5. Shell nearly cylindrical; spire thick, 

 lengthened; aperture small. 



Subgenus Leptolimnea, Swainson. 

 L. Kirilandiana, Lea, L. lanceata, Gould. 



6. Shell very slender, spire attenuated, whorls 

 flattened, oblique ; aperture produced, ex- 

 panded, without fold, 



Subgenus Acella, Hald. 

 L. gracihs, Jay. 



(61) 



