STROPHIA. 221 



Pupa incana, Binney, Terr. Moll., I. 109 ; III. PI. LXVIII. — Leidy, T. M. U. 



S., 1. PL XV. Figs. 2-4, anat.— Pfeiffer, Mai. Blatt., II. 13; Mon. Hel. 



Viv., IV. 657. — W. G. Binney, Terr. Moll., IV. 140, PI. LXXIX. Fig. 17 ; 



L. & Fr.-W. Sh., I. 247, Fig. 430 (1869). — Tryon, Amer. Journ. Conch., III. 



308(1868). 

 P21pa.rn.umia, Potiez and Michaud, Gal., I. 169, PI. XVII. Figs. 1 -2 (teste 



Pfr.). 

 Pupa viarilima, y, Pfeiffer, Mon. Hel. Viv., III. 539. — Gould, in Terr. Moll. 



II. 316. 

 Pupa detrita, Shuttleworth, MS., Pfeiffer, in Mai. Blatt., I. 158 (1853); I. 



205 (1854), PI. III. Figs. 9, 10. 



A Cuban and Bahamas species, found in the Florida Subregion, both on the 

 southern part of the mainland, and on the Keys, from Cape Florida to Key West. 



Animal whitish, brownish, smoky, or nearly black, darker on the back and 

 upper part of head. Body finely granulated, the granules arranged in regular 

 lines longitudinally, making the surface look as if minutely and longitudinally 

 furrowed. Eye-peduncles rather short, slender, bulbous at the extremities ; 

 tentacles very short. 



This species is found plentifully at Key West, where it inhabits low grounds 

 near salt-water ponds. It attaches itself to saline plants, a few inches from the 

 soil. At other times it retreats under stones. It is probably confined to the 

 vicinity of the ocean. It has also been found on other neighboring Keys, and 

 on the mainland from Key West to Cape Florida. The animal varies much in 

 color ; it is shy when kept in confinement. In winter it forms a membranous 

 epiphragm. 



The general appearance of this shell is cylindrical, with both extremities ob- 

 tuse. The width of the central whorls is nearly uniform ; the upper only be- 

 come gradually narrower to the apex. The number of whorls is usually about 

 9, but sometimes 12 ; and the progressive increase of the width of the whorl, 

 in revolving from the apex to the aperture, though regular in each specimen, 

 differs so much in different specimens, that some shells are very short and 

 robust, while others are long and fusiform. The whorls are nearly flat, the 



surface shining, and marked with numerous angular stria?, which, 



° ° Fig 126. 



on the back and last whorl, attain sometimes the prominence of 



wrinkles. The peristome is often very thick ; it is not added until 



the shell has acquired at least seven or eight full volutions. The 



outline of the external aperture is an oval, whose greatest diameter 



is parallel with the axis of the shell, truncated obliquely by the 



columellar margin ; internally it is modified by a lamellar tooth or 



fold on its superior parietes, and another marking the depression 



of the axis ; when these are prominent, the outline of the throat of 



the aperture is somewhat trilobate. One or both of the teeth are sometimes 



wanting. The apex of the spire is corneous. Its color is chalky or horny 



white, with frequently a livid brown tint beneath. 



