LIMN^A. 95 



cannot be specifically separated from reflexa ; 

 it might, however, retain its name as a beauti- 

 ful variety. The species appears to extend 

 through all the north-western States, but does 

 not inhabit the waters flowing into the Pacific 

 Ocean, being there replaced by an allied, but 

 distinct species, L. Rowellii. 



10. LTMN^A ATTENUATA, Say. 

 Hald. Monog. 28, t. 9, figs. 1, 5. 



11. LIMN^A ROWELLII, Tryon. 

 Plate 17, fig. 1. 



Shell elongate, narrow, consisting of six 

 rather obliquely revolving whorls ; spire some- 

 what attenuately lengthened; apex acute; 

 suture not much impressed ; aperture not half 

 the length of the shell, oblique; columella 

 with a distinct fold, turned to the left below, 

 and appressed to the body the whole distance ; 

 surface rather smooth and polished ; texture 



fragile. 



(69) 



