186 American Seashells 



Orbigny is /4 to /4 inch in length, with its umbilicus not so much covered, 

 and it may be only a form of this species. 



Polinices ififmaculatus Totten Immaculate Moon-shell 



Gulf of St. Lawrence to North Carolina. 



% inch in length, subovate, smooth, milk-white and glossy when de- 

 prived of its thin greenish-yellow periostracum. The ivory-white, thickened 

 callus does not encroach upon the small, round, deep umbilicus. Operculum 

 corneous, thin, light-brown. Commonly dredged off New England, and 

 often found in fish stomachs. 



Polinices bnmneiis Link Brown Moon-shell 



Plate 5) 



Southeast Florida (rare), West Indies (Texas?). 



I to 2 inches in length, heavy, glossy-smooth, with a deep, white umbili- 

 cus and small, low spiral callus. Exterior tan to orange-brown. Operculum 

 corneous, thin, amber-brown. 



Polinices uberinus Orbigny Dwarf White Moon-shell 



North Carolina to southeast Florida and the Caribbean. 



^ inch in length, very similar to lacteiis, but the umbilical opening is 

 larger, the callus is button-shaped and located against the columella near the 

 center, and there is a large, rounded ridge running back from the callus into 

 the umbilicus. Commonly dredged from 15 to 100 fathoms. Rarely in beach 

 drift. 



Subgenus Neverita Risso 1826 

 Polinices duplicatus Say Shark Eye 



Plates 5k; 22h 



Cape Cod to Florida and the Gulf States. 



I to 2>2 inches in length, glossy-smooth; umbilicus deep but almost cov- 

 ered over by a large, button-like, brown callus. Color slate-gray to tan; base 

 of shell often whitish. Columella white. The shell is generally flattened and 

 much wider than high, but some specimens (pi. 2 2h) are as wide as high and 

 globose in shape. Operculum corneous, brown, and thin. This is a very com- 

 mon sand-lover found along our eastern coasts. Compare young specimens 

 with Natica livida. 



