HELIX. 



183 



ScBOENus POMATIA, (Leacli) Beck. 



Shell imperforate or subimperforate, globose, striate, horny- 

 calcareous, generally banded ; whirls 4-6, convex, the last large, 

 ventricose, descending ; aperture lunate-orbicular, peristome 

 patulous or straight, within labiate with callus, the columellar 

 margin reflected, generally callous. 



Helix aspersa, Muller. — Shell imperforate, subglobose, rather thin, 

 the surface rather coarsely and irregularly striate, and finely wrinkled and 

 indented ; the ground-color is yellowish 



or grayish, with chestnut-colored bands -pis. 322. 



of various width, across which are narrow 

 undulating llammules of yellowish ; the 

 spire is rather obtuse, composed of four 

 or five moderately convex whirls, the 

 principal one being very large and ven- 

 tricose.; the aperture is large, a little 

 oblique, rounded lunate ; the peristome 

 white, sharp, turned slightly outward, 

 and in the region of the umbilicus turn- 

 ing over the columella in a broad ap- 

 pressed callus, which is continued to the Uelix asptrsa. 



upper junction of the peristome. Greatest 

 diam. 32, height 22 mill. 



Helix aspersa, Mullek, Verm. II, 59. — Pfeiffer, Mon. Hel. Viv. I, 241. — 

 DeKay, N. Y. Moll. 47 (1843).— Binney, Terr. Moll. II, 117, not in 

 plate.— W. G. Binney, Terr. Moll. IV, 51, pi. Ixxvii, f. 4. 



Pomatia aspersa, Tkyon, Am. Journ. Conch. II, 322, pi. vi, f. 16 (1866). 



In gardens in Charleston, S. C, where it still exists. Also 

 has been found at New Orleans ; Portland, Maine; Nova Scotia; 

 Santa Barbara, California. It is an 

 European species, accidentally intro- 

 duced into this country. 



Moquin-Tandon describes the jaw 

 of H. aspersa as slightly arcuate, 

 somewhat attenuated towards the 

 blunt ends ; anterior surface with 

 stout, distant ribs, denticulating either margin. 



Fig. 323. 



Jaw of Selix aspersa, yonng and 

 mature. [Moqcin-Tandon.] 



