134 FAUNA AMERICANA. 



Genus. 



Arvicola^ Lacep. Cuv. Desm. 



Lemmus, Geoff. 



HypudoBus, Illig. 



MuSj Briss. Linn. Erxleb. Bodd. 



CHARACTERS. 



{r Incisor 2. 

 superior 8. < Canine 0. 

 inferior 8. ^ Canine 0. 

 C. Molar 6. 



Incisors of the upper jaw large, cuneiform ; the 

 inferior sharp. 



Molars compound ; crowns marked with zigzag 

 lines of enamel ; the largest situated anteriorly, 

 the smallest posteriorly. 



Fore feet having the rudiment of a thumb, and 

 four toes furnished with weak nails ; the posterior 

 with five toes, armed with claws, not palmated or 

 furnished with hairs on their borders:^ 



Tail hairy, cylindrical, nearly as long as the 

 body. From eight to twelve pectoral and ven- 

 tral mammae. 



Habit. Burrowing in the earth, feeding prin- 

 cipally on grain and bulbous roots ; some are om- 

 nivorous. 



Inhabit both the old and new continent. 



Species. 

 1. ,/Jrvicola amphibius. 



