HELIX. 



•79 



Helix idaboensis, Newcomb. — Shell wmbilicated, globosely ele- 

 vated, thick, white, rough, with stout, distant, oblique, curving, blunt 

 ribs, of which twenty-eight are upon the last whirl ; 

 suture impressed ; spire highly elevated ; apex waxen, ^ig. 138. 



smoother, obtuse ; whirls five, convex, the last equally 

 globose above and below, hardly falling before ; um- 

 bilicus moderate, one-sixth the lesser diameter of the 

 shell ; aperture oblique, almost circular ; peristome 

 simple, made almost continuous by a heavy parietal 

 callus connecting its approximating ends, that of the 

 columella slightly expanded and reflected over a por- 

 tion of the umbilicus. Greater diam. 13, lesser 11 ; 

 height 7 mill. ffelix idahoensis- 



Helix idahoensis, Newcomb, Am. Journ. Conch. II, 1, 



pi. i, f. 1-3 (1866). 

 Anguispira idahoensis, Tkyon, Am. Journ. Conch. II, 260, pi. iv, f. 54 (1866). 



Idaho Territory, between Idaho City and Coeur d'Alene 

 mining district. 



The shell figured was received from Dr. Newcomb. The 

 species in texture and form resembles somewhat a small elevated 

 HeliJ) cooperi. 



Helix perspectiva, Say. — Shell broadly and perspectively um- 

 bilicated, orbicular, scarcely convex above, excavated below, thin, reddish 

 horn-color, regularly ribbed ; whirls six and a half, gradually 

 increasing; aperture small. Innately subcircular, within Fig. 139. 

 furnished with a single subprominent tooth on the base of 

 the shell ; peristome simple, acute, its extremities separated 

 widely. Greater diam. 8, lesser 7j ; height 3 mill. 



Helix perspectiva, Say, Journ. Phila. Acad. I, 18 (1817) ; 

 Nich. Encycl. IV, ed. 3 (1819) ; Binney's ed. 9.— 

 BiNNEY, Bost. Journ. Nat. Hist. Ill, 430, pi. xxi, f. 4 

 (1840) ; Terr. Moll. II, 256, pi. xxx, f. 1.— DeKay, 

 N. Y. Moll. 42, pi. iii, f. 38 (1843).— Ferussac, Tab. 



