HELIX. 151 



varying width, sometimes uniform chestnut color ; whorls 5-6, very 

 convex, the last considerably deflected *at the aperture; lip white, 

 narrowly reflected, dilated into the umbilicus. Diam. 25 mill. 



Western and Northwestern United States. 



H. PENNSYLVANICA, Green. PL 31, figs. 52-54, 



Imperforate, turbinately subglobose, rather thick, closely obliquely 

 striate, suture distinct, bright horn color; whorls 6, convex; aperture 

 subtriangular, lip white, narrowly reflected, slightly thickened 

 internally at the base ; umbilical region indented. 



Diam. 13-18 mill. 



Western Pennsylvania to Illinois. 



More turbinate, with more triangular aperture than the next 

 species. 



H. MITCHELLIANA, Lea. PL 31, figs. 55, 56. 



Imperforate, subglobose, moderately thick, translucent, finely 

 striate, shining, yellowish horn color, suture not deep ; whorls 5, the 

 last well-rounded, contracted behind the lip above, but the groove 

 becoming indistinct towards the base; aperture rounded, lip 

 white, narrowly reflected; base very convex. Diam. 15 mill. 



Virginia, No. Carolina, Ohio, Kentucky. 



H. CHBISTYI, Bland. PL 31, figs. 63, 64. 



Imperforate, depressed, solid, with close, oblique, rib-like striae, 

 dark horn color; whorls 4J, somewhat convex, descending in front, 

 periphery a little angular, base convex, excavated in the middle; 

 aperture with a strong parietal tooth. Diam. 10 mill. 



J/fx. Cherokee Co., N. Carolina; Georgia; E. Tennessee. 



H. EXOLETA, Binney. PL 32, figs. 65-67. 



Ventricose, suborbicular, whorls 5-6, heavy, suture well-marked, 

 body whorl large and convex; aperture rounded, lip reflected, 

 parietal "wall toothed ; umbilicus covered by the extremities of the 

 lip ; light horn color. Diam. 25 mill. 



Western N. York to Georgia, and westward to Missouri. 



It is H. zaleta, Say, of Binney. 



H. WHEATLEYI, Bland. PL 32, figs. 68, 69. 



Imperforate, thin, closely ribbed-striate, with microscopic gran- 

 ulations, hirsute; whorls 5i convex, the last well rounded, slightly 

 depressed and constricted at the aperture, base cpnvex, umbilical 



