€HAZY LIMESTONE. 31 



52. 2. PLEUROTOMARIA BIANGULATA. 



Pl. VI. Fig. 6. 



Subdepressed-spiral ; lengtli and breadth about equal ; volutions few, ventricose, bi- 

 angulated above and somewhat rounded below ; suture canaliculated ; aperture somewhat 

 quadrangular ; cast smooth, rounded. ^ 



The specimen is imperfect, but presents very clearly the above characters : it is the only 

 one of the species seen in tiiis rock. 



Position and locality. Chazy, Clinton county, in the lower grey limestone. 



{State Collection.) 



53. 3. PLEVROTOMARIA {Species undetermined). 



Pl. VI. Fig. 8. 



One or two fragments of the under side of a species, apparently referable to this genus, 

 have been seen, but nothing from which a description can be satisfactorily made out. The 

 surface is strongly striated. 



Position and locality. In the fine-grained grey limestone of Chazy, Clinton county. 



(Slate Collection.) 



54. 4. PLEUROTOMARIA ANTIQUATA ( n. sp.) . 



Pl. VII. Fig. 1. 



Trochiform, subconical ; volutions about three or four, depressed laterally. 



The specimen is a cast, two and a half inches in diameter, and nearly two inches high ; 

 the last volutions wanting. The surface markings are entirely wanting, and no portion of 

 the shell remains to indicate its external characters. Since this is the only large species 

 observed in this rock, it will readily be recognized. 



Position and locality. In the dark-colored limestone, associated with Maclurea magna. 

 Chazy, Clinton .county. 



55. 1. CAPULUS AURIFORMIS. 



Pl. VI. Figs. 6 a, b. 



Depressed -spiral ; apex scarcely elevated ; whorls about tliree, the last one embracing 

 nearly the whole shell, flattened-ventricose, marked by a few undulations ; no striae visible ; 

 aperture large, semilunar ; shell thick. 



A single specimen only of this shell has been observed : it is much depressed, with a 

 large aperture ; the outer whorl rapidly attenuating to the apex. The shell is evidently 

 waterworn ; and any stria, if they existed, are obliterated. 



Position and locality. Galway, Saratoga county, in the Chazy limestone. 



(State Collection.) 



