178 



NORTH AMERICAN INDEX FOSSILS. 



become strong and spread over several ribs in the first part of the 

 loose-coiling whorl, but become smaller again towards the aper- 

 ture; a second row of nodes more distant occurs near the small 

 umbilicus; in the typical form the nodes of both rows continue 

 over entire last whorl ; in the variety the tubercles of the outer 



Fig. 1430. Scaphites nvdosus var. quadrangularis, X 3 +• (After Meek.) 



row increase and diminish rapidly and do not cover the entire 

 whorl, while the inner row has few nodes. 



Widely distributed in the Montanan of western North America, 

 and also in the Ripleyan of New Jersey. 



298. S. nodosus quadrangularis (Meek). (Figs. 1429, 1430.) 



Cretacic. 

 Small, more nearly subquadrangular in section of whorl ; venter 

 flattened, nodes weak, and of but slight extent in each row. 

 Montanan of Dakota, Kansas, etc. 



299. S. hippocrepis (DeKay). (Fig. 1431.) Cretacic. 

 Rapidly enlarging in last whorl, and as rapidly contracting to 



Fig. 143 1. Scaphites hippocrepis. (After Whitfield, Pal. N. J., 2.) 



