64 AMERICAN JOURNAL 



DESCRIPTIONS OP MIOCENE SHELLS OP THE ATLANTIC 



SLOPE. 



BY T. A. CONRAD. 



MURICIDiE. 



MUREX, Lin. 



Subgenus PTERORHYTIS, Conrad. 



M. UMBRIFER, Conrad. — PL 5, fig. 7. 



Description. — Fusiform, with four very prominent, lamelliforrn 

 ribs on the body whorl ; whorls 6, angular, with a prominent re- 

 volving rib on the angle ; two small ribs, the lowest one obsolete, 

 on the body whorl, distant from the upper one ; aperture ovate, 

 surrounded by a raised margin, with a prominent, erect tooth 

 near the base of the labrum ; canal closed. 



31. umbrifer, Conrad, Tert. Fossils, p. 17, pi. iii, fig. 1. 



Locality. — Day's Point, James River, Va. Rare. 



TYPHIS, Montfort. 



T. acuticosta, Conrad. — PI. 5, fig. 6. 



Description. — Fusiform, whorls 5, spire scalariform, promi- 

 nent ; one set of ribs on the body whorl prominent, acute, ex- 

 tending to the base ; the alternate ribs shorter, rounded ; aper- 

 ture ovate, margined by a prominent rim ; beak narrow. 



Murex acuticosta, Conrad, Journ. Acad, Nat. Sci., vol. vi, p. 

 217, pi. 9, fig. 1. 



Locality. — St. Mary's River, Md. 



SYCOTYPUS, Browne. 

 S. incile, Conrad. — Pi. 6, fig. 2. 



Description. — Subpyriform, profoundly ventricose ; whorls 6 



