HELIX. 



163 



Fig. 281. 



Helij: hillebrandi. 



Helix liilleTjffaiBdi, Newcomb.— Shell umbilicated, biconvex, or- 

 bicularly depressed, carinated ; yellowish horn- 

 color, with a chestnut band within two white ones, 

 showing only in the aperture, granulated, finely 

 striate and hirsute ; spire subpyramidal ; whirls 

 six, slightly convex, the last carinated at its middle, 

 inflated below, slightly descending ; aperture ob- 

 lique, lunate, snbangulate, white and banded with- 

 in ; peristome white, thickened, reflected, partially 

 concealing the open umbilicus, ends approached. 

 Greater diam. 25, lesser 19 ; height 10 mill. 



Helix hillebrandi, Newcomb, Proc. Cal. Acad. Nat. 

 Sci. in, 115, 181 (1864). 



Aglaja hillebrandi, Tryon, Am. Journ. Couch. II, 

 310, pi. V, f. 7 (1866). 



Tulumne Co., California. 



The specimen figured is from Dr. Newcomb, 



Subgenus ARIONTA, Leach. 



Shell iimbilicately-perforate, conic- or depressed-globose, thin; 

 whirls 5-6, the last gradually descending ; aperture lunate- 

 rotund ; peristome broadly labiate, its margins parallel, the basal 

 dilated, often covering the umbilicus. 



Animal (of H. townsendiana) corpulent, gradually taperino-- 

 color pale yellowish-green ; surface with rather sparse, feebly- 

 developed, elliptical granules, not seeming to have any regular 

 arrangement ; margin of disk rather broad, granulated, but 

 regularly marked with radiating furrows. 



Fig. 282. 



Helix arrosa, Gould. — Shell globose conic, thick, umbilicated, 

 indented, and minutely granulated ; color 

 reddish-olive, varied with yellow, and with 

 a fuscous revolving band ; whirls seven, 

 convex ; aperture roundly ovate ; peristome 

 reflected, flesh-colored ; throat bluish. Diam. 

 40, height IS mill. 



Helix aniginoso, Gould, Proc. Brfet. Soc. 



V, 127 (1855) ; Terr. Moll. Ill, 12.— 



W. G. BiNNEY, Pac. R. R. Rep. VI, 

 • 11<> (1857). Belix arrosa. 



