66 STEPPE FAUNAS AND TEMPERATE 



burrows in companies. With the vegetable food they 

 mingle insects and the eggs and young of birds, 

 especially of the steppe lark. 



The jerboas of the genus Dipus chiefly inhabit the 

 hot deserts further south, but some species, notably 

 D. sagitta, extend into the steppes. Though the habits 

 of the members of this genus are generally similar to 

 those of the preceding in their coloration and in their 

 intolerance of rain or damp, they are essentially in- 

 habitants of arid regions (cf. p. 133). 



In the steppe region are also found the hamsters 

 (Cricetus), with a western extension into Europe. But 

 though originally doubtless steppe animals, the ham- 

 sters, hke the brown and black rats, though to a less 

 extentj have attached themselves to man, and find it 

 more profitable to plunder his fields and gardens, than 

 to depend upon the precarious vegetation of the steppes. 

 They are remarkable for the size and elaboration of 

 their burrows, in which they store quantities of corn, 

 &c., for winter use. 



Another characteristic genus of the steppe is Lagomys, 

 the genus which includes the picas, tailless hares or 

 whistling hares as they are variously called. These 

 animals are smaller than a rabbit, and are for the most 

 part mountain animals, living high up among rocks 

 and stones in the mountains of Central Asia. In Siberia, 

 however, they are found on lower ground, and even 

 extend into the tundra region. They form a very 

 important part of the food of the carnivores of the high 

 steppe, replacing here the lemming of the tundra. In 

 Mongolia, L. ogotona occurs in large colonies, and at 

 the approach of winter stores up large quantities of 

 hay near the openings of the holes. According to 

 Prejevalski, these haystacks may weigh 10 kilogrammes 



