IS 



LAND AND FRESH-WATER SHELLS OF N. A. [PART I. 



Helix tenuistriata, Binney, Bost. Journ. Nat. Hist. 1842, IV, part 1, cover, 

 p. 3.— Pfeiffer, Mon. Hel. Viv. I, 432.— \V. G. Bis.ney, Terr. Moll, 

 IV, 118. 



Helix vortex, teste Gould (non Pfeiffer), Terr. Moll. Ill, 34. 



This is an unknown species ; the above description is copied 

 from manuscript of Dr. Binney. 



Helix cooperi, W. G. Binney.— Shell nmbilicated ; elevated, glo- 

 bose ; solid, coarse and rough with oblique incremental striae intersected 

 with delicate spiral lines ; color white, variously marked with a single 

 narrow band, or broader longitudinal and spiral patches of reddish-brown ; 



Fig. 132. 



Fig. 133. 



Fig. 134. 



Fig. 135. 



Fig. 136. 



Fig. 137. 



Helix cooperi. 



suture impressed ; spire elevated ; whirls five, convex, the last rounded, 

 very decidedly deflected at the aperture; umbilicus moderate, pervious, 

 one-fifth the greater diameter of the shell ; aperture very oblique, circular ; 

 peristome simple, thickened, with its extremities very nearly approached, 

 and joined by a heavy white callus, that of the columella reflected. 

 Greater diam. 20, lesser 1 6 ; height 13 mill. 



Helix cooperi, W. G. Binney, Proc. Acad. Nat. Sci. Phila. 1858, 118 ; 

 Terr. Moll. IV, 97, pi. Ixxvii, f. 11.— Pfeiffer, Mai. Blatt. 1859, 6. 

 Anguispira cooperi, Tryon, Am. Journ. Conch. II, 2G0, pi. iv, f. 52 (1866). 



Black Hills of Nebraska and in the central basin from New 

 Mexico to lat. 48°. 



The species varies greatly in shape, as seen in the figures given 

 of various forms. It is sometimes strongly carinated, and the 

 peristome is sometimes made continuous by the heavy, raised 

 callus connecting its extremities. 



