LAMELLIBEANCHIATA FROM BASE OF UPPER MARLS. 209 



ASTARTID^. 



Genus CARDITA Brug. 



Cardita intermedia, n. sp. 

 Plate XXVIII, Figs. 14 and 15. 



Form of cast transversely elliptical, or transversely ovate, exclusive of 

 the beaks, largest at the posterior end. Valves very ventricose, with strong 

 projecting beaks, which in this condition are moderately distant. Hinge- 

 line arcuate. Anterior end narrowly rounded; posterior end more broadly 

 rounded; basal margin strongly curved. Muscular scars on the cast small 

 but distinct; margin of the cast showing indications often or twelve rather 

 strong radiating ribs between the muscular scars. 



This is a very ventricose form, and has had strong, enrolled, subanterior 

 beaks, which have been directed slightly upwards as well as forward. The 

 surface has been marked by strong radiating ribs corresponding nearly to 

 those of C, perantiqua of the Eocene marl in strength and number. The 

 form of the shell has been somewhat like that of that species, so far as can 

 be determined from the beautifully preserved cast figured; but the beaks 

 have not been directed so decidedly anteriorly, nor has the shell been so sub- 

 quadrangular in outline. These features will serve readily to distinguish be- 

 tween the two. 



Formation and locality. — In the lower layers of the Upper Marl Bed, 

 at Farmingdale, New Jersey. The specimen is from the collection at 

 Columbia College. 



Genus CRASSATELLA Lamarck. 



Crassatella Conradi, n. sp. 



Plate XXVIU, Figs. 1-5. 



Comp. GrassateHa curta Conrad'? Proc. A. N. Sci-., 18G2, p. 578. Am. Jour. Coneb., 

 Vol. II, p. 104, PL VIII, Fig. 2. 



Shell, as known from internal cast, small, and of a quadrangular form, 



with ventricose valves and moderately prominent beaks, which are situated 

 4418 MON 9—14 



