374 P. i£ Raymond — Fauna of the Chazy Limestone. 



A large specimen is 27 mm long and 26 mm high. Another is 

 43 mm long and 39 mm high. A small one is 10 mAl long and 10 mm 

 high. 



The species is easily recognized by the curved anterior mar- 

 gin and the great convexity. The line of greatest convexity 

 follows the anterior margin. There is an elongate posterior 

 muscle faintly outlined on some of the casts. The general 

 appearance is somewhat like Ambonychia amygdalina Hall. 



Locality. — Yalcour Island, Chazy, and Sloop Island, New 

 York. 



Conocardium beecheri sp. nov. 



Shell very small but robust, with long anterior and short 

 posterior wings. The region of greatest convexity is from the 

 beak straight to the base of the shell, the curvature decreasing 

 gradually forward to the anterior wing and rather abruptly 

 backward to the posterior wing. The anterior wing is long, 

 with straight lower margin. The posterior wing is short and 

 narrow, joining the body at a large angle. The surface is 

 marked by 7 or 8 large plications on the anterior wing, 15 or 

 20 smaller ones on the body of the shell, and 3 or 4 very large 

 ones on the posterior wing. The dimensions of 2 specimens 

 are: First, length 6-5 mm ,' height 5 ram ; second, length 6 mm , 

 height 4 mm . 



Locality. — Sloop Island, east of Yalcour Island, N ew York ; 

 also on Yalcour Island and at Chazy, Clinton Countv, New 

 York. 



Modiolopsis fabaformis sp. nov. 



Shell small, thick, with a strong ridge extending from the 

 umbo to the lower posterior angle. In front of this ridge is a 

 deep depression, which continues to the middle of the ventral 

 margin,' making that margin sinuate. Anterior ear small, 

 convex. Anterior margin narrowly rounded. Posterior mar- 

 gin broadly rounded, not oblique as in Modiolopsis brevias- 

 cula and M. parviuscida. The surface is marked by numer- 

 ous concentric lines of growth. 



Locality. — Common in the upper layers at Yalcour Island. 

 The type specimen is in the writer's collection. 



Modiolopsis sowteri sp. nov. 



Shell of medium size for the genus, rather convex, with a 

 strong ridge running back from the beak to the lower posterior 

 angle. Toward the front is a slight depression running from 

 just ahead of the beaks a little backward to the basal margin. 

 In front of the beak is a very deeply impressed anterior scar, 



