38 



bands, the last near the base ; wlurls very bulging. 

 The beginning of new peristomes is marked by prom- 

 inent lines or ridges. Length one and one-fourth inches, 

 Loc. Illinois River. 



This elegant species has caused much dispute among 

 our naturalists, some claiming that it is identical with 

 a well known European species ; among these is Mr. 

 Geo. W. Tryon. I am inclined to think, however, 

 that the weight of evidence is in favor of Mr. Binney's 

 views. 



VIVI1»ARA SUBPI RPl KKA, Say, 



Shell oblong ; whirls live, wrinkled ; apex obtuse ; 

 suture impressed ; color greenish with a purplish tinge •, 

 spire lengthened ; shell has three reddish bands ; length 

 three-fourths of an inch. Found in the Illinois river. 



This species maybe distinguished from any other by 

 the unusual expansion of the last whirl, and the red- 

 dish bands which are prominent in some specimens, 

 but obscure in others. 



GE:\II« MKt.A:\THO, BowuiTCH. 



:»icia«ti.o dcci«««. Say. Shell elongated, ovate, 

 whirls six ; peristome acute, lines of growth plain ; 

 apex missing in full grown specimens ; color green ; 

 aperture oval, oblique, bluish within ; length one and 

 one-fourth inches. Quite abundant in Fox and Illinois 

 rivers, and also in the Vermillion river. 



We sometimes find here a shell corresponding to 

 Pahidina lieierostropha, Kirtland. The shell is sin- 

 istral ; has five whirls ; suture is distinct ; color green ; 



