RODENTIA. 139 
Gmelin has already separated from them the Marmots, Dormice, 
and the Jerboas; but we carry their subdivision much further, from 
considerations founded on the form of their grinders. 
Arctomys,(1) Gm. 
The Marmots, it is true, have the inferior incisors pointed like 
those of the greater number of animals comprehended in the great ge- 
nus Mus; but their grinders, like those of the Squirrel, amount to five 
on each side above, and four below, all bristled with points 5 accord- 
ingly, some species are inclined to eat flesh and feed upon insects, 
as well as grass. There are four toes and a tubercle in place of a 
thumb to the fore feet, and five toes to the hind ones. In other re- 
spects these animals are nearly the direct reverse of the Squirrels, 
being heavy, having short legs, a middle sized or short hairy tail, 
and a large flat head, passing the winter in a state of torpor, and 
shut up in deep holes, the entrance of which they close with a heap | 
of grass. They live in societies, and are easily tamed. Two spe- 
cies are known in the eastern continent. 
Arct. alpinus; Mus alpinus, L.; Buff. VIII, xxviii. (The 
Alpine Marmot.) Large as a Hare; tailshort ; fur yellowish 
grey, with ash coloured tints about the head. It lives in high 
mountains, immediately below the region of perpetual snow. 
Arct. bobac;'M. bobac, 1..; Pall. Glir. V; Schreb. CCIX. 
(The Bobac.) Size of the preceding; of a yellowish grey, 
tinted with red about the head. Inhabits low mountains and 
hills, from Poland to Kamschatka, and frequently digs its bur- 
row in the hardest soil.(2) 
America also produces some species. 
Arct. monaz; Buff. Supp. II, xxviii. (The Maryland 
Marmot.) Grey ; tail blackish, as well as the top of the head. 
Arct. empetra, Pall.; Schreb. CX. Less than the preceding ; 
grey ; red beneath. 
SPERMOPHILUS, Fred. Cuv. 
We apply this name to those Marmots that have cheek pouches. 
The superior lightness of their structure has caused them to be 
called Ground Squirrels. Eastern Europe produces one species: 
M. citillus, L.; Buff. Supp. II, xxxi. (The Souslik or Zizel.) 
A pretty little animal, of a greyish brown, watered or mottled 
(1) Arctomys, Bear-Rat. 
(2) Russian Travellers in Bucharia mention some other Marmots, fret. fulvus, 
Aret. lepto-dactylus, Arct. musogaricus, which are not yet perhaps sufficiently distin- 
guished from the Bobac or from the Souslik. 
