VIVIPARA. 



Vivi2)ara suhpur- 

 purea. 



Mr. Say's original specimens of this species Fig. 56. 



are still preserved in the collection of the Phi- 

 ladelphia Academy. Fig. 56 is taken from one 

 of them. 



The surface is often quite smooth and shining, 

 the spire more or less elongated and slender, but 

 always distinguished by the penultimate whirl, 

 which is very much larger than is usual in our 

 Viviparse, and when seen from behind, appears 

 remarkably bulging at its upper portion. Fig. 

 55 is copied from one of Mr. Say's figures. 



In the description of the animal Mr. Say speaks of a tubular 

 cylindrical organ as a respiratory syphon, but Haldeman sug- 

 gests its being probably the outlet of the viscous glands. 



A specimen in Mr. Anthony's cabinet measures in extreme 

 length 33, last whirl 19, penultimate 8, antepenultimate 2^ mill., 

 the measurements being taken on the front of the shell. 



I have traced this species from Texas through Louisiana and 

 Mississippi to Key West, Florida, and in the Western States of 

 Indiana, Wisconsin, and Missouri. 



A more elongated, slender form of the species, which is common 

 in the southwest, from Mississippi to Texas, has been described 

 by Mr. Tryon as a distinct species under the name of V. Texana. 

 A careful examination of the specimen from which 

 his diagnosis is drawn, as well as the large series 

 in the Smithsonian collection, leaves no doubt in 

 my mind of its identity. The original description 

 and figure are given below. 



Fig. 57. 



Vivipara texana. 



Vivipara Texana. — Shell solid, conic, light green co- 

 lored ; spire elongate, suture deeply impressed, apex ob- 

 tuse ; whirls 6, slightly convex ; aperture small, subor- 

 bicular, equalling two-fifths the shell's length. 



Texas. Coll. Acad. Nat. Sciences ; Coll. G. W. Tryon, jr. 



Shell solid, narrowly conic, consisting of six whirls, 

 which are somewhat flattened around the upper half of their breadth ; 

 suture well marked ; aperture suborbicular, equalling two-fifths of the 

 length of the shell ; umbilicus covered ; epidermis light green with faint 

 red revolving bands. 



This shell resembles most the V. subpurpurea, Say, but is easily distin- 

 guished by having six whirls, which are much narrower than in that spe- 

 3 



