76 



NEW YORK STATE MUSEUM 



Leptodomus prunus Clarke 



Plate 16, figure 6 



Leptodomus prunus Clarke. N. Y. State Mus. Bui. 107. 1917. p. 225 



Elongate shells with anterior umbones and low cincture most distinct 

 at the beaks. Surface quite evenly convex though the beaks are depressed. 

 Umbonal ridge broad and ill defined. Ornament consisting of concentric 

 ridges, sharp in the umbonal region and with closely crowded concentric 

 lines between all, becoming obscure toward the margins. Length of each 

 valve about twice the hight. 



This species is distinguished from L. canadensis Billings of the 

 Grande Greve limestone by its shallower cincture, but further knowledge of 

 the species may show its very close relationship to L . striatulus F. 

 Roemer of the upper Coblentzian. [For figures of the latter see Beushausen. 

 op cit. p. 265, pi. 24, fig. 12-14] 



Locality. Telos lake, Blind Cove point, Me. 



Cypricardinia magna Clarke 



or 

 cf. crenistriata Sandberger 



Plate 13, figures 12, 13 



See Sandberger. Verstein. d. rhein. Schichtensystems. 1850-56. p. 263, pi. 28, fig. 5 

 Beushausen. Lamellibr. d. rhein. Devon. 1895. p. 178, pi. 16, fig. 9-13 

 Cypricardinia magna Clarke or cf. crenistriata Sandberger. N. Y. State 

 Mus. Bui. 107. 1907. p. 229 



Shell large for this genus, somewhat variable in outline but usually 

 obliquely rhomboidal with very strong umbonal ridge, anterior beaks, very 

 decided postumbonal slope which is deeply incurved, narrow anterior extrem- 

 ity widening backward. Hinge somewhat curved, shell extended behind, 

 lower margin slightly incurved and sinuate. Length and greatest hight as 

 six to five, actual length 30 mm, hight 25 mm. Some specimens are quite 

 erect with the hight and length equal. Surface bearing strong, concentric, 

 lamellose and quite regular sculpture, on which the finer ornamental lines 

 occurring in man)' other species have not been retained. 



This shell in its size and proportions is very closely like C. crenis- 

 triata as figured by Beushausen from the lower and upper Coblentzian 

 of the Rhine. Species in the Grande Greve limestone (C. distincta 

 Billings) attain its size and C. p Ian u lata Hall (Schoharie grit) has a 

 similar contour but no other form than that above cited is known to us 

 which approaches it both in size and contour. 



Locality. Moosehead lake, Baker Brook point, Me. 



