536 



NORTH AMERICAN INDEX FOSSILS. 



Helderbergian : New York. 

 485. C. indenta Conrad. (Fig. 729, c.) Devonic. 



Length more than one third greater than height. Hinge line 

 straight and oblique. 



Onondaga : New York, Falls of the Ohio, Ontario. Abundant 



Fig. 729. 



a, b, Cypricardinia consimilis, right and cardinal views; c, C. 

 indenta. (N. Y. Surv. ) 



Also in Lower 



in Hamilton of New York, Pennsylvania, Virginia. 

 Devonic of Nevada. 



486. C. consimilis Hall. (Fig. 729, a, b.) Mississippi. 



More elongate than C. indenta, with comparatively, 

 narrower posterior end and less sinuate basal margin. 



Waverlyan : Pennsylvania, Ohio. 

 487. C. carbonaria Meek. (Fig. 730.) Carbonic. 

 Small. Surface marked with 15 to 20 flattened, 

 subimbricating concentric ridges. 

 Ohio, Kansas, Missouri, Colorado. 



Fig. 730. 



Cypricardi- 

 nia carbona- 

 ria. (Kan. 

 Pal., VI/II.) 



CXXXIV. Astartella Hall. 

 Shell thick, smooth or concentrically furrowed. Lunule im- 

 pressed. Two cardinal teeth present in each valve ; the posterior 

 tooth in the right valve has a longitudinal pit on the summit. 

 Ligament external. Carbonic. 

 488. A. vera Hall. (Fig. 731.) Carbonic. 



Fig. 731. 

 Fig. 732. 



Astartella vera. (Kan. Pal., VI/II.) 

 Astartella newberryi. (Pal. Ohio, II.) 



Surface marked with strong concentric furrows separated by 

 sharp angular ridges. 



Coal Measures : Ohio-Oklahoma. 

 489. A. newberryi Meek. (Fig. 732.) Carbonic. 



