and roiiiidecl in front. Cardinal line usually straight, and 

 not oblique. Umbonal slope a strong angular ridge, from 

 the beak to the post-inferior margin. A broad, undefined 

 cincture separates off the anterior portion. A strong car- 

 dinal tooth in the left valve fits into a depression in the right 

 valve. Ligament external. 



GoxioPHORA MODioMORPHOiDES. Grabau. (Fig. 168.) 

 (1898: Rep't X. Y. State Geol. 1896: Faun. Ham. Gr., 

 p. 2r.l:. ) 



Distill Li;uishing Cliarncttrs. — Arcuate cardinal line; pro- 

 nounced arcuate umbonal ridge, 

 with the surface above the 

 ridge flat or slightly concave; 

 small anterior end, scarcely 

 extending beyond the beaks ; 

 numerous strong, regular lines 

 T. .a^ r' ■ X, A- , ,7 of growth. 



Fig. 168. Goniophora modiomorphoides. ~ 



A characteristic right valve. (Original.) FoUud lu tllC EuCriual limC- 



stone, at Section 5 (where it is common). 



Gex[s CYPRICARDELLA. Hall. 



[Ety. : Diminutive from Cypricardia, Cyprina and Cardium.J 

 (18.")6: Trans. Albany Inst.. Vol. IV.) 



Shells with equal. ine(iuilateral valves, which are trans- 

 versely sub-elliptical ov sub-quadrate in outline. The car- 

 dinal line is straight or arcuate, the anterior end narro^^•ed 

 and rounded, and the posterior end broad and truncate. A 

 more or less defined umbonal ridge extends from the small 

 pointed beak to the posterior basal angle. Ligament ex- 

 ternal ; cardinal teeth, one in each valve. 



Cypricakuella bellistrl\ta. (Gonrad. ) ( Fig. 169. ) 

 (Pal. N. Y., Vol. v., Pt. 1., p. 308, Pis. XLH., LXXHL, 

 LXXIV.) 



Distinguishing Clmracters. — Projecting rounded anterior 

 end, with a distinct dejii'ession, or lunide, below the beak ; 



