HYALINA. 



43 



Hyalina Ijreweri, Newcomb. — Shell umbilicated, depressed, 

 smooth, shining, surface unbroken by the wrinkles of growth, 

 very light horn-color ; spire scarcely elevated ; whirls four, pig. 66. 

 flattened, the last depressed, shelving towards its base ; um- 

 bilicus moderate ; aperture transversely lunar ; peristome 

 simple, acute. Greater diam. 5, height 2^ mill. 



Helix breweri, Newcomb, Proc. Cal. Acad. Nat. Sci. Ill, 118 



(1864). 

 Hi/alina hreiceri, Teton, Am. Journ. Conch. II, 250, pi. iv, f. 



27 (1866). 



Near Lake Tahoe, California. 



My figure is drawn from an authentic specimen. 



Fig. 67. 



Hyalina chersinella, Dall. — Shell narrowly umbilicated, de- 

 pressed, transparent, lightest horn-color, shining, with distant 

 incremental wrinkles : spire slightly elevated ; whirls four, 

 scarcely convex, the last depressed-globose ; umbilicus nai;'- 

 row, pervious ; aperture oblique, lunately-subcircular ; peri- 

 stome simple, acute. Greater diam. 3, height 1 mill. 



Helix (Conulus) chersinella, Dall, Am. Journ. Conch. II, 



328, pi. xxi, fig. 

 Conulus chersinella, Tryon, Am. Journ. Conch. Ill, 162, pi. 



xi, f. 33-35 (1867). 







HyaJina 

 chersinella. 



" Big Trees," Calaveras County, California. 

 The description and figure are drawn from an authentic 

 specimen. 



Subgenus MESOMPHIX, Raf. 



Shell umbilicated or perforated, globosely-depressed, thin, 

 striated, reddish horn-color, lighter below, shining ; whirls 4^6 ; 

 aperture lunar ovate ; peristome simple, 

 straight, acute, extremities approach- 

 ing, that of the columella subreflexed. 



Animal (of ZT. ligera) nnUorm h\a,ck- "^H&i^^^c^a 



ish slate-color over the whole upper Ammml oi Ilyalina libera. 



Fig.68. 



