348 A PROPOSED CLASSIFICATION OF THE GENUS HELIX. 
labrum white, narrow, extending to the base of the umbilicus, and 
slightly contracting it ; labium: with a compressed white tooth; um- 
bilical region deeply indented; greatest breadth 3 inch. Canada. 
The hair-like projections, Dr. Gould says, are often wanting at. 
every stage of growth.* 
Some objections may be raised against a classification of this kind, 
such as the finding at times of shells normally without teeth with 
teeth ; but these are exceptions and by no means common. JH. albo- 
labris has been frequently found in the United States with a small 
tooth. I have examined a great many Canadian specimens and as yet 
have not found one with this peculiarity. This difficulty is, however, 
easily obviated by placing such shells in each division under their 
proper sections—the description of course being attached to the sec- 
tion it normally belongs to. 
Again, some shells are found occasionally with the umbilicus nearly 
or entirely covered, as in H. fraterna (Say) ; this peculiarity is very 
rare. I only know of it occurring in fraterna. It can be got over in 
the same manner as pointed out above. 
As regards dividing the shells into large and small, I have taken 4 
inch as the division line. ‘his division is not a very good one on 
account of the variation in size of many shells, but it in some mea- 
sure helps the object in view, as it places fewer specimens under each 
head. . 
I do not pretend to say that this classification is a perfect one; if it 
assists in the more ready determination of species it has amply ful- 
filled my object. It is more a classification of convenience than a 
strictly scientific one. Those who have made a study of Conchology 
will see its imperfections, but I hope at the same time they will turn 
their attention to perfecting some good classifications of not only the 
genus Helix, but of the other large genera. 
* None of the above descriptions are as full as the originals. I have given what I think 
to be the most important parts, sufficient to distinguish the shells one from another. 
I have made brief descriptions of hortensis, striatella, nulchella, and hydrophila, from 
specimens in my possession, not having seen any descriptions of them. 
A few more species besides those described in this paper are found in Lower Canada, viz... 
H, Sayti (Binney), H. asterieus (Morse), and H, exoleta (Binney)s 
