MAMMALIA, 157 
dark brown colour, except their bellies, which are white ; their tails are not so long as those of 
the gray squirrels, but are shaped the same.’ In page 93 of the first volume of Lewis and 
Clark’s narrative, where the animal is termed petit chien, it is stated that “ The head resembles 
the squirrel in every respect, except that the ear is shorter; the tail like that of the ground 
squirrel; the toe-nails are long; the fur fine, and the long hair is gray.” In the third 
volume, where it is called barking squirrel, the following particulars are mentioned :—* This 
animal commonly weighs three pounds ; the colour is an uniform, bright brick-red and gray, and 
the former predominates; the under side of the neck and belly are lighter than other parts 
of the body; the legs are short, and the breast and shoulders wide ; the head is short and 
muscular, and terminates more bluntly, wider, and flatly than the common squirrel ; the ears 
are short and have the appearance of amputation ; the jaw is furnished with a pouch to contain 
his food, but not so large as that of the common squirrel* ; each foot has five toes, and the 
two outer ones are much shorter than those in the centre. The two inner toes of the fore-feet 
are long, sharp, and well adapted to digging and scratching. From the extremity of the nose 
to the end of the tail, this animal measures one foot and five inches, of which the tail occupies 
four inches,” 
Of the five preceding Marmots, the Arctomys Empetra has a slight folding of the 
lining of the mouth, forming the rudiment of a cheek-pouch ; the A. pruinosus 
has not been examined; the presence or absence of cheek-pouches in the A, 
brachyurus is not noted by its describers; the ‘ ample’ cheek-pouches of the 
A. monazx rest on the authority of Dr. Godman; and those of the A. Ludovicianus 
are mentioned by Lewis and Clark alone, whilst their having escaped the notice of 
so accurate an observer as Mr. Say, excites some doubt of their existence. The 
Spermophiles, described in the following pages, have all cheek-pouches, which, 
indeed, furnish the only character that distinguishes the sub-genus from the other 
marmots. The solitary mode of life attributed to the Spermophiles, and some 
other peculiarities, apply principally to A. citillus, and so many species have 
been added since M. F, Cuvier first described the genus Spermophilus, that its 
characters require to be re-modelled. 
* It is not easy to divine what the ‘* Common Squirrel” is which has ample cheek-pouches, 
