OF CONCHOLOGY. 235 



DESCKIPTION OP A NEW SPECIES OE HELIX. 



BY "WESLEY NEWCOMB, M, D. 



Helix {IfacrocycUs,) Voyana, Newcomb. — t. 25, f. 4. 



Bescrij^tion. — H. testa late umbilicata, depressa, pallida cor- 

 nea, minute oblique striata, parum nitida, sub-diaphana; spira 

 obtusa, sub-planulata; anfr. quinque, convexis, ultimus latus, 

 declivatus, antice sub-descendens; apertura sinuato-truncato- 

 ovalis; peristomate reflexiusculo,juncturam superiorem angu- 

 lato, antice valide sinuoso decumbente, cum lamina prominente 

 connectante. 



Dimensions. — Diam. maj. "50, min. -40, alt. "20 pol. 



ffahitat. — Canyon Creek, Trinity Co., California (Voy.) 



Shell broadly umbilicate, depressed, pale liorn-color, mi- 

 nutely obliquely striate, slightly shining, translucent; spire 

 obtuse, nearly on a plane; whorls 5, convex, the last large, 

 and shelving down, in front slightly descending; aperture 

 sinuate, truncately ovate; lip a little reflexed, angulated at its 

 juncture with the body whorl above, farther forward strongly 

 bent down, a strong plait or elevated ridge on the body whorl 

 connecting the outer and inner lips. 



Remarks. — This little shell bears the nearest relationship to 

 S. Vancouvereivsis, Lea, {vellicata, Forbes,) of any other, spe- 

 cies inhabiting the Pacific coast. It is found in the same 

 neighborhood with that species, which there attains its normal 

 Oregon size, differing in this respect from its diminutive de- 

 velopement in the neighborhood of San Francisco, specimens 

 of which have been distributed under the erroneous name of 

 S. sportella, Gould. 



It differs from that species in the curious development of 

 the aperture, which is a constant character in adult speci- 

 mens, and in its comparatively small size. 



