586 



ZOOLOGY. 



as a muskrat, is nocturnal in its habits and, therefore, rarely 

 seen, and burrows in the earth, feeding on roots. 



The lowest in intelligence are, perhaps, the hares, rep- 

 resented by the common varying hare {Lepus America- 

 nus Erxleben, Pig. 505), of which an interesting variety, 

 L. Bairdii, lives on the Alpine summits of the Eocky Moun- 



^:p^^, 



Fig. S06.— The Spalax or Blind Eat.— After Owen. 



tains. The largest of all existing rodents is the Capy- 

 bara of South America, which looks like a pig. This is 

 succeeded by the porcupine, which either lives in trees or 

 burrows in the earth, while the more intelligent, active 

 forms are the beaver, muskrat, the European blind rat 

 {Spalax, Fig. 506) the rats and mice, squirrels, and lastly 



the marmots. The domes- 

 tic mouse and the two rats,, 

 the brown or Norway rat 

 {Mus decumanus Pallas), 

 the black rat {Mus rattus 

 Linn.), and the common 

 house mouse {Mus muscu- 

 lus Linn.), are cosmopoli- 

 tan animals. The jumping 

 mouse (Fig. 507) has remarkably long hind legs and short 

 fore legs. Peculiar to the western plains is the prairie-dog, 

 {Gynomys ludovicianus) which represents the marmots of 

 the Old World ; it is semi-social and takes in perforce as 

 boarders the owl and rattlesnake, which devour its young. 



Pig. 507.— Jumping Mouse (Zapus hud- 

 sonius). — From Tenney's Zoology. 



