THE SEWELLEL. 99 
Tail, very short, concealed by the fur of the hips, mammas six, the 
anterior pair situated between the fore legs. 
Habits. — Form small societies, feeding on vegetable substances, and 
living in burrows. — Richardson. 
There is only one species belonging to this genus known at present. 
The name aplodontia is derived from owrXoos, aploos, simple, and o8ovg, odous, 
a tooth. 
APLODONTIA LEPORINA.-Rich. 
The Sewellel. 
PLATE CX XI II.— Male. 
A. Fuscescens, magnitudine Leporis Sylvatici, corpore brevi robusto, 
capite magno, cauda brevissima. 
CHARACTERS. 
Size of the gray rabbit (Lepus Sylvaticus). Body, short and thick ; head, 
large ; tail, very short. Colour, brownish. 
SYNONYMES. 
Sewellel. Lewis and Clark, vol. iii. p. 39. 
Arctomys Ruea. Harlan, Fauna, p. 308. 
“ “ Griffith, Cuv. Animal Kingdom, vol. v. p. 245, species 636. 
Aplodontia Leporina. Rich, Zool. Jour., No. 15, p. 335. January, 1829. 
— Sewellel. Rich, Fauna Boreali Americana, p. 211, pi. 
18 c, figs. '7-14, cranium, &c. 
DESCRIPTION. 
Body, short, thick, and heavy, nearly reaching the ground ; legs, short ; 
head, large ; nose, thick and blunt, densely covered with hair to the 
nostrils, which are small and separated by a narrow furrowed septum 
concealed by the hair. 
Mouth, rather small ; incisors, large and strong ; lips, thick, and clothed 
with rigid hairs ; a brush of white hair projects into the mouth from the 
upper lip near its union with the lower one ; whiskers, strong, and longer 
than the head ; a few stiff hairs over the eyes, on the cheeks, and on the 
outer sides of the fore-legs ; the eye is very small ; the external ear rises 
