8o Cincinnati Society of Natural History. 



It is in the collections of both authors, but the type belongs 

 to Mr. Faber. Found in the Hudson River Group, near the 

 top of the hills, in Cincinnati. 



MODIOLOPSIS I.ONGA, n. sp. 



Plate /, /vV. 2, left side vieic; Fii^. ^, cardinal vie~a\ natural 

 size. 



Shell very loni;-, gradually enlarging from the front to the 

 posterior third, and even widening posterior to this: hinge 

 line straight, basal margin nearly straight in the middle part 

 of the shell ; cardinal and basal lines gradually converge from 

 near the posterior end to the beaks ; height greater than the 

 thickness ; anterior and posterior ends rounded ; a flattened 

 area exists below and behind the beaks extending obliquely 

 to the basal margin, but it does not produce any contraction 

 of the basal margin. Beaks near the anterior end of the shell 

 and extending beyond the cardinal line. Umbones quite small 

 and umbonal ridge soon disappearing in the graduallj' increas- 

 ing ventricose character of the valves behind the beaks. Mus- 

 cular impressions small and very little below and anterior to 

 the beaks. The casts at hand do not preserve any of the sur- 

 face markings, though the casts are in a good .state of preser- 

 vation. External shell unknown. 



This species is distinguished by its general elongated form, 

 converging basal and cardinal lines, undefined umbones, and 

 expanding and wedge-shaped posterior end. There is no 

 defined species with which it can be confounded. 



Found by Charles Faber, in the Hudson River Group, on 

 the hills, at Cincinnati, and now in his collection. 



MoDiOLOPSis sin.cAT.v, n. sp. 

 /'late /, /•"/<,'. 7, left side rieie, natnral si:e. 



vShell about medium si/.e, elongate, subelliptical in (nilline : 

 height greater than thickness; both anterior and po.sterior 

 ends rounded ; cardinal line .slightly arched behind the beaks; 

 basal margin broadly and gently rounded. Basal margin very 

 slightly contracted by a shallow undefined cincture, that arises 



