GASTROPODA— -PLEUROTOMARIIDJE. 



633 



95. L. wisconsinensis Ulrich and Scofield. (Fig. 858.) 



Ordovicic. 



All except apical whorls loose-coiled and free ; carinae obsolete 

 towards lip. 



Stones River of Minnesota, Wisconsin, and Illinois. 



B. Lines of growth forming strong peripheral reentrant, with ^>-shaped notch. 



Fig. 857. Lophospira helicteres, last, non-coiling portion of large specimen and 

 nearly complete individual ; s, sutural edge. (After Salter, Can. Organ. Rem. 

 Dec, I.) 



96. L. perangulata Hall. (Fig. 859, a-c.) Ordovicic. 



Small, embracing to within one half or two thirds the shoulder 

 width of the periphery, last whorl often free, shoulder slightly con- 

 cave ; apical angle 50 to yo°; band prominent, trilineate ; lower 

 carina pronounced ; umbilicus small. 



Stones River of Kentucky, Tennessee, Minnesota ; Lowville of 



FlG. 858. Lophospira wisconsinensis. (After Ulrich and Scofield, Pal. Minn.) 



