RODENTIA. | 147 
preferring the bottom lands of high grounds. It excavates 
galleries, and removes the earth to some distance from the open- 
ing. Its magazines, which are principally filled with the roots 
of the wild carrot cut into two inch pieces, are frequently two 
feet in diameter. 
A. arvalis ; Mus arvalis, L.; Buff. VII, xlvii. (The Campag- 
nol.) Size of a Mouse; of a reddish-ash colour ; tail not so long 
as the body. It inhabits holes which it excavates in the earth, 
where it collects grain for the winter. The multiplication of 
this animal is sometimes so excessive as to cause much injury. 
Al. cconomicus, Mus economicus, Pall. Glir. XIV, A; 
Schreb. cxc. (The Meadow Campagnol.) A little darker 
coloured, and the tail somewhat shorter. It lives in a sort of 
oven-shaped chamber formed under the turf, from which issue 
several narrow and ramifying canals running in various direc- 
tions; other canals communicate with a second cavity which 
contains its provisions. From all Siberia. It is thought to 
have been found in Switzerland and in the south of France, 
particularly, as we are assured, in the potatoe fields.(1) See 
Append. X of Am. Ed. 
Gerorycuus, Illig. 
Or the Lemmings, Cuv. have very short ears and tail, and the 
toes of the fore feet peculiarly well formed for digging. 
The two first species have five very distinct nails to each of 
the fore feet, like the Rat-Moles and the Jumping-Hare. 
G. lemmus ; Mus lemmus, L.3; Pall. Glir. XII, A. B. Schreb. 
cxcv. (The Lemming.) A northern species, as large as a Rat, 
with black and yellow fur, very celebrated for its occasional 
migrations in innumerable bodies. At these periods they are 
said to march in a straight line, regardless of rivers or moun- 
tains; and while no obstacle can impede their progress, they 
devastate the country through which they pass. Their usual 
residence appears to be the shores of the Arctic ocean. 
G. vulgaris ; Mus aspalax, Gm., Pall. Glir. X, Schreb. CCV. 
(The Zocor.) Reddish-grey; the three middle nails of the fore 
feet long, arcuate, compressed and trenchant, for cutting earth 
(1) Here most probably would come the M. sazatilis, alliarus, rutilus, gregalis 
and socialis, Pall. Glir. But the MZ. Jagurus and torquatus come nearer to the 
Lemmings. ‘There are several Field-Rats or Campagnols in North America, such 
as the Arvicola xanthognatha, Leach, Miscel. 1, pl. xxvi—Arvicola pennsylvanica, 
Wilson, Amer. Ornith. VI, pl. 1, F. 3.—4rv. palustris, Harl. &c. Better figures 
and new and comparative descriptions of the preceding species are much wanted. 
