EXPLANATION OF PLATK XXX. 



CrIOCERAS LEPTC7S, Eth. fit. 



Fig. 1. Lateral view of portion of a whorl with a broad, almost flat Hank, 

 traversed by regular hardly sigmoidal nontuberculate costse. 



,, 2. Ventral view of Fig. 1, displaying the narrow venter and compressed 

 outline ; the costa? are practically straight on crossing the former. 



,, 3. Dorsal view of Figs. 1 and 2, exhibiting the Hat costate dorsum 

 destitute of groove, the costa' bent slightly forward, and the longi- 

 tudinally obtusely triangular section. Compare this with the 

 section of a typical C. jackii (Plate xxxii., tig. 1). 



(Figures slightly less than natural size.) 



