G58 Systematic Paleoxtology — UrrEu Devonian" 



angle over umbo. Anterior extremity nearly on a line with middle of 

 length of valve; posterior margin rormding somewhat abruptly to ventral 

 margin. Sliell quite convex, umbo full, rounded ; surface sloping regul- 

 larly from umbo to margins, umbonal ridge rounded, not distinct. Shell 

 massive. Interior shows an oblique tooth in left valve corresponding to 

 a depression in right valve; pallial line distant from margin. Surface 

 ornamented by faint concentric lines. 



Length 20-25 mm.; height lG-19 mm. 



This species approaches C. gregaria but differs in its more massive 

 shell, marked pallial line, more elliptical and less rhomboidal shape, 

 umbonal slope scarcely angular. 



Occurrence. — Jennings Formation, Chemung Member. Williams 

 Eoad, on Polish Mountain, 2142 ?; Town Creek, 2122 ?, 2228 ? abun- 

 dant: Millstone, 27G1 abundant. 



Collection. — ^Mai'vland Geological Survey. 



Cypricardella ? sp. 



Description. — Several impressions and exteriors and interiors indicate 

 the presence of another species of this genus of transversely elongate 

 form, with fine concentric surface striations and low postumbonal ridge 

 situated close uj^on the postlateral slope. The outline of the shells ap- 

 proaches that of C. teniiistriata Hall, a Hamilton and Ithaca species 

 in New York, but in the position of the posterior ridge they are distinct. 

 The material obtained is insufficient for final determination. 



Length 38 mm.; height 22 mm. 



Occurrence. — Jennings FoRiiATiON, Chemung Member. National 

 Eoad a few miles west of Frostburg. 



Collection. — Maryland Geological Survey. 



