18S5.] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 275 



Subfamily AuiiicuLiNiE. 



Foot not divided transversely. 



Geuus Carychium Mliller. 



Shell cyliEdro-coiiical, mimite, one denticle and the usual plait on 

 the columella ; lip thickened, reflected, sometimes with one or two ob- 

 tuse denticles; nucleus hemisrdierical, immersed; internal septa of the 

 spire persistent or but slightly absorbed ; tentacles short, obtuse ; the 

 eyes sessile at their inner bases; foot entire obtuse behind; muzzle 

 bilobed, extending in advance of the foot. Type G. minimum Miiller, of 

 ]i^urope.* (Zool. Dan. Prodr., p. 242, 1776.) 



Genus Aueicula Lamarck. 



Shell large, strong, witli thick epidermis ; aperture with a large pari- 

 etal plication behind that belonging to the columella ; a strong jiarietal 

 callus; the outer lip and peristome thickened but not dentate or Urate; 

 internal septa partly absorbed. Animal blind, with rather long tentacles 

 swelled at the distal end; foot entire, simple. Type Auricula auris- 

 midw Lamarck (Prodr., p. 71, 1799). 



Subgenus Auriculastrum Fischer. 



Shell smaller, thinner, and smoother; animal with eyes; tentacles 

 rather short, subconic ; foot simple. 



Type A. subula Quoy. (Fischer. Man., p. 498, 1883.) 



Auriculastrum pelluceiis Meukc. Plate 18, fig. 8. 

 f Auricula Dominicensls F6r., Tab!., p. 103, 1822. 

 Auricula 2)elluce)is Meiike, Syu. Meth. Moll., p. 131, 1830; Bland, Ann. Lye. 



Nat. Hist. N. Y., xi, p. 87, 1874. Not of Pteeve. 

 ^Auricula ceylovica Reeve, Concli. icon. Auricula, No. 5, j)!. 2 (as of A. Adams, 



P. Z. S., 1854, p. 10). 

 Not Auricula pallescens Ree^e, 1. c, as of Petit, P. Z. S., 1854, p. 10. 



Habitat. — Demerara, Menke ; Guadalupe Island, West Indies, Beau ; 

 Cedar Keys, Fla, Calkins ; Punta Easa, Prime ; Oyster Bay, Hemphill. 



There seems to be some confusion in E^eeve, which I have not the 

 books and specimens to unravel. There is no likelihood of the Ceylon 



* Carnchium exigumn Say, the common form of the United States, has not yet been 

 reported from Florida, but doubtless will be found there. The nucleus of this species 

 is so little advanced toward a whorl -wheu the regular spire begins that it at first 

 seems as if this genus formed an exception to the family rule of having a sinistral 

 nucleus. It is, however, only superficially so. In C. minimum the immersion is often 

 very recognizable, and some specimens of our species show it better than others. 

 The teeth in C. cxiguum are often deficient, but the columellar plait always exists, 

 though perhaps not visible without breaking the shell. In L. and F. W. Shells of N. 

 Am., ii, p. 7, Mr. Binney has tiikea the bilobed prolongations of the muzzle for an 

 anterior division of the foot. Fig. 7 on the same page is very poor, and even inaccu- 

 rate. See Plate 18, fig. 14, this volume. 



