42 PALJBONTOLOQY OF NBW FORK. 



LoXONEMA ? TERES. 

 PLATE Mil, FIU. 10. 

 Loxonema teres, Hall. Illustrations of Devonian Fossils: Gasteropoda, pi. 13. 1876. 



Shell turretiform. Volutions seven or more, gradually enlarging from the 

 apex, the last one moderately ventricose, and all gently rounded on the 

 periphery. 



The specimen is essentially a cast of the interior, retaining some portions of 

 the shell in a crystalline condition. The general aspect of the cast is that of 

 Loxonema, and it is thus referred with some doubt. It is slightly fusiform, the 

 upper volutions being proportionally more contracted than those below. Tbe 

 greatest diameter of the last volution is about equal to the height of the suc- 

 ceeding three volutions. 



This form bears much resemblance to the L. subattenuata, but the volutions 

 are a little more closely enrolled and slightly more convex on the periphery. 

 It is possible, however, that a greater number of specimens may show a grada- 

 tion, uniting these forms as a single species. 



Formation and locality. In limestone of the Upper Helderberg group, at Clar- 

 ence Hollow, Erie county, N. Y. 



LOXONEMA PEXATA. 



PLATE XIII, FIGS. 16, 18(11,12?!. 



Loxonema pexaia. Hall. Fourteenth Rep. N. Y. State Cab. Nat. Hist., p. 104. 1861. 

 " " " Illustrations of Devonian Fossils: Gasteropoda, pi. 13. 1876. 



Shell elongate, terete or subfusiform. Volutions six or more, gradually 

 [landing from the apex, somewhat flattened on the upper half, or a little 

 concave just below the suture, and most convex below the middle ; £he 

 last one moderately ventricose. Aperture subelliptical. 



Surface marked by strong, regular, elevated striae, which cross the volutions 

 in a gentle curve, turning backward from the suture ami again forward, 

 making the curve at about one-third of the distance from the upper side 



