A PROPOSED CLASSIFICATION OF THE GENUS HELIX. 343 
A PROPOSED CLASSIFICATION OF THE GENUS HELIX. 
BY A. E. WILLIAMSON. 
Among the mollusca there are many genera containing a large 
number of species. Of the fresh water varieties, the genus Unio has 
over 300 representatives ; the genus Melania from 200 to 250; and 
the genus Lymneea, although not nearly so numerous as either of the 
preceding, is still a very important division. Of the land shells the 
genus Helix bears off the palm in point of numbers, having upwards 
of 1500 species; the genera Bulimus, Pupa, and a few others also; 
present many varieties. 
It will be seen by these facts that considerable difficulty may be 
encountered in arriving at the name of any species, even though we 
be well supplied with works of reference; for the labour of wading 
through a number of descriptions is not a very pleasing task, and it 
is only by figures of the shells, by well filled museums, by notes pub- 
lished in scientific journals, or by long practice and study, that we can 
get over this difficulty. 
How much easier it would be, and, at the same time, prevent us 
from becoming disheartened at the long list of descriptions we may 
have to read over before finding the name of any shell, if some good 
classification could be adopted under which the shells might be 
grouped. This, I think, would in a great measure obviate the diffi- 
culties mentioned above. In following out this idea I have attempted 
the following classification of the genus Helix :— 
DIVISION I. 
SHELLS TOOTHLESS. 
Section A.—Umbilicus closed or wanting. 
Sus-Sec. A.—Shells large, over 4 inch in diameter. 
1. Lip reflected. 
H. aLBouaBRis (Say).—Whorls about 53, with rather obtuse 
wrinkles, crossed by very minute lines, more obvious on the body 
whorl than on the spire; shell pale reddish brown; labrum (outer 
lip) widely reflected, fiat, and white; breadth 1 inch. Canada. 
H. worrensis (Miller).—A variety of H. nemoralis. Whorls 
about 5, rounded, wrinkled ; shell thin and light ; white, yellow, with 
