72 LAND AND FRESH-WATER MOLLUSKS. 
Genus Limax (Limaz, a slug). 
The Limaces differ little from the Arions, but 
are destitute of a mucous pore at the end of the 
tail; the mantle is concentrically marked and not 
granulated, and the respiratory aperture near the 
hind part of its border; the tail is carinated, or 
ridged. 
The horny jaw of Limaxz (fig. 12) is strongly 
arched, smooth and rostrated in 
Za 5 front; it differs markedly from that 
palaakiynsy OF Arion, and resembles that of 
L.gagates. HHelrcella (fig. 18) and Vitrina. 
The species feed chiefly on tender herbage, 
fruits, and vegetable substances in general; they 
are very voracious, feeding after rain, or in the 
evening to early morn; during the heat of the 
day they remain concealed, and during droughts 
and frosts they are torpid, buried underground. 
They are the great pests of our gardens and 
cultivated lands,—to young oats, peas, tares, 
clover, and turnips, they give preference ; and 
many fields have been made barren by them, 
and have had to be ploughed down and resown. 
Although vegetables are the legitimate food of 
the slug, most of them are occasionally carni- 
vorous, not from necessity, but from pure and 
decisive choice; some of them may be even 
convicted of cannibalism. They have, however, 
