700 



NORTH AMERICAN INDEX FOSSILS. 



Coal measures of Iowa, Indiana, Illinois, Ohio, and Arkansas. 



310. S. planus White. (Fig. 1006, e, f.) Carbonic. 

 Shorter and more convex than S. fusiformis ; columellar fold 



strong. 



Coal measures of Ohio, Illinois, and New Mexico. 



311. S. newberryi Stevens. (Fig. 1006, g, h.) Carbonic. 

 Shorter and more convex than preceding ; columellar folds 



double. 



Coal measures of Illinois, Iowa, and Missouri. 



312. S. paludinaeformis Hall. (Fig. 1006, i.) Carbonic. 



Fig. 1006. a, b, Soltniscus typicus ; c, d, S. fusiformis ; e,f S. planus ; g, k, S. new- 

 berryi; i, S. paludinceformis ; j, k y S. brevis. (All after White, 13th Ind. Rep.) 



Short and thick ; spire short but gently concave ; body whorl 

 large, ventricose ; columellar fold strong. 



Coal measures of Iowa, Indiana, Ohio, and Missouri. 



313. S. brevis White. (Fig. 1006, j, k.) Carbonic. 

 Small, short and thick, with very convex body whorl. Ap- 

 proaches Splicer odoma. 



Coal measures of Iowa, Missouri, Illinois, and New Mexico. 



314. S. gracilis Cox. Carbonic. 

 Like the preceding, but more slender and with much higher 



spire. 



Coal measures of Iowa, Missouri, and Kentucky. 



315. S. regularis Cox. (Fig. 1007.) Carbonic. 

 Large, with long spire of nine convex volutions. Body whorl 



