P. E. Raymond — Fauna of the Chazy Limestone. 369 



Camarotoechia major sp. no v. 



Outline somewhat oval, widest a little in front of the mid- 

 dle. Dorsal valve with 10 to 14 strong angular plications. 

 The ventral valve has 9 to 14. The fold and sinus are hardly 

 denned except by a gentle arch in front, but are outlined on 

 both valves by a pair of very strong plications. The dorsal fold 

 bears 5 plications, the middle one of which is the strongest. 

 The ventral sinus has 4 plications, the 2 largest in the middle. 

 The ventral beak is somewhat incurved. 



Length of a good specimen 23 mra ; width 21 mm . 



Locality. — Southeast point of Valcoivr Island, New York. 

 The type is in the writer's collection. 



IStrophomena prisca sp. nov. 



Shell of medium size, resupinate, nearly as long as wide. 

 Ventral valve convex at the umbo, flat in front to about the 

 middle of the valve and then concave. Dorsal valve flat on 

 the umbo and convex in front. Cardinal area narrow, the wide 

 clelthvrium mostly covered by the deltidium, with a small open- 

 ing for the pedicle at the beak. Muscle area in the ventral 

 valve small, confined to the space under the umbo. Surface 

 marked by fine alternating strise, the prominent ones being 

 very numerous and increasing by implantation. Between each 

 pair of the strong strise are two or three finer ones and the 

 whole surface is crenulated by fine concentric strioe. The dor- 

 sal valve sometimes shows very small concentric wrinkles. 



One specimen is 15 -o mm long and 20 mm wide ; another 16' rjin 

 long and 19 - 5 mm wide. 



Locality. — All the specimens are from Valcour Island, New 

 York, and are in the writer's collection. 



Orthis ignicula sp. nov. 



Shell transversely oval in outline, usually but little wider 

 than long. Hinge width nearly equal to the greatest width 

 of the shell. Ventral valve strongly convex, the area high 

 and a little incurved. 



Dorsal valve nearly flat, with a broad depression near the 

 front. Area of dorsal valve rather wide. Cardinal process 

 small. Delthyrium narrow and open. Surface marked by 16 

 to 25 direct rounded plications which increase by implanta- 

 tion. 



Locality. — Found rarely on the southeast corner of Valcour 

 Island, New York. 



