8 



Family CARDIOMORPHID^E. 



EDMONDIA ALBEKSI, D. sp. 



Plate /, Fig. 9, right valve; Fig. 10, left valve of another speci- 

 men; Fig. 11, cardinal view of same specimen with point 

 of beak of left valve broken off, and beak at 

 right valve broken off. 



Species rather large, six specimens at hand, one smaller and one 

 larger than either one illustrated. Shell subcircular, our speci- 

 mens are casts, and the length and height aresubequal. Cardinal 

 line is gently curving, anterior end somewhat sharply rounded, 

 posterior end subtruncate, shell most produced at the posterior 

 lower margin. Beaks a little forward of the central part, high, 

 and curving over the cardinal line. Umbones high, anterior and 

 posterior sides subangular, the angularity merging below into the 

 general convexity of the shell. Yalves somewhat gibbous in the 

 middle part. Pallial line curves quite regularly and is near the 

 margin. Surfaces of the casts retain the evidences of five concen- 

 tric lines on the shell. 



We have little doubt about the generic reference of this species, 

 though the hinge is unknown, and it bears no near resemblance, 

 in form, to any other described species. 



Found by R. A. Blair, in the Chouteau limestone, at Sedalia, 

 Missouri, and now in the collection of S. A. Miller. The specific 

 name is in honor of Mr. A. Albers, a very good palaeontologist as 

 well as an excellent artist. 



CHiENOMYA LONGA, n. sp. 



Plate I, Fig. 12, cardinal view; Fig. 13, left valve. 



Species medium size. Shell more than three times as large as 

 high. Cardinal line concave, less than half the length of the 

 shell. Ligament external. Anterior end narrowly rounded and 

 closed. Posterior end widely gaping, dilated and produced nearly 

 half the length of the shell, from the end of the hinge line, to 

 the postero-basal margin. Basal margin nearly straight, though 

 slightly constricted in the middle part. Beaks near the anterior 

 end, somewhat acute and incurved. Umbonal area depressed and 

 from which arises a broad undefined cincture, that extends to the 

 basal margin. Post umbonal slope angular, but gradually loses 



