E 
424 Binney's Monograph of the Helices 
Synonyms AND REFERENCES. 
Helix eléctrina, Gould. Mollusca of Massachusetts, 
(Unpublished. ) 
DESCRIPTION. 
Animal. Not noticed. 
Shell. Small, depressed, thin, fragile ; epidermis 
amber-colored, wrinkled, shining ; whorls four, -the 
last rapidly enlarging towards the mouth ; aperture 
rounded; lip simple, its edge rather thickened, not 
acute ; wmbilicus small, but well marked and con- 
stant. 
Greatest transverse diameter more than one s eighth 
of an inch. : 
GEOGRAPHICAL Disrrisution. Found hitherto - 
on the shores of Fresh Pond, near Boston. 
Remarks. For the following remarks I am in- 
debted to Dr. Gould. “ In size, the depressed-conical 
Shape of the upper surface, the number of whorls, 
and the rapid enlargement of the largest ‘whorl, this 
shell corresponds with Heurx indentata. It differs 
in its darker, smoky horn-color, its constant umbili- 
cus, its rather thick and shining lip, and in its whitish : 
wrinkles, which, instead of being remote, are crowded. 
From Heurx arborea it differs in having one whorl 
less, the last one rapidly dilating, its apex not being 
depressed, its thinner structure and more glossy sur 
face, and in its somewhat smaller umbilicus. In 
Hrrix arbórea the lip has a flexuous curve, but is 
nearly a direct section of the whorl in this. Though 
n of the same size and general appearance, the three 
Lo á 
EY 
