WeJler — Kinderhook Faimal Studies. 31 



description of Cardiopsis there are said to be two distinct 

 anterior teeth in each valve. 



C. radiata from the goniatite beds of Rockford, Indiana, 

 is the only species of the genus which has been properly illus- 

 trated, although two others are recognized, C. jejuna Win., 

 from Michigan, and C. megambonata Win., from Michigan 

 and from the Yellow Sandstone at Burlington, Iowa. The 

 last of these is possibly not distinct from G . radiata. The 

 Northview specimens are lower and rounder than the figures 

 of C. radiata , hni the illustrations exibit some variation in 

 this characteristic, and as the full extent of the variation 

 cannot be determined from the literature, it is thought 

 unwise to propose a new specific name for our shells. 



Cardiopsis? erectus n. sp. 



PI. HI. f. 3-4. 



Shell obliquely subovate in outline, attaining a height of 

 20 mm. in the largest specimen examined, moderately convex; 

 the two valves equal, beaks prominent, highly elevated, erect, 

 incurved but not convolute at the tips and directed forward 

 with a concave area between the beak and the hinge-line. 

 Anterior and posterior margins rounded, basal margin 

 slightly flattened. Hinge-line arcuate, edentulous, less than 

 the greatest length of the shell. Surface of the shell covered 

 with numerous fine, simple, rounded costae, which are some- 

 what coarser upon the posterior umbonal slope. Between 

 sixty and seventy costae maybe counted upon the type speci- 

 men. Besides the radiating costae there are a few concentric 

 wrinkles, irregular in position and in intensity. 



Remarks. This species is similar to the last, but may be 

 distinguished by its less gibbosity, its erect beaks, and its 

 concentric wrinkles. The absence of hinge-teeth would seem 

 to exclude the species from Cardiopsis, and possibly it should 

 be placed in the genus Dexiobia which is said to be " eden- 

 tulous ( ?) " in the original description, leaving this character- 

 istic somewhat in doubt. The equal valves of the shell, 

 however, are against placing it in Dexiobia and it is therefore 

 referred provisionally to Cardiopsis, leaving the final decision 

 until a time when all the species of these genera from various 



