JERBOAS AND JUMPING MICE. 



45 



little animals called jerboas. In company with a few 

 species of birds and reptiles, they seem to be the only 

 inhabitants of this barren and "thirsty land." Ac- 

 cording to the accounts given by the Arabs, the exten- 

 sive and intricate burrows of this animal, consisting, 

 as they do, of many branched passages dug out in the 

 hard, dry soil, not far from the surface, are the result 



Jerboas. 



of the joint exertions of the whole community, which, 

 if true, is the only case known of any mammal, except 

 building and occupying communal dwellings. 



man, 



On the least alarm the jerboas vanish into these un- 

 derground villages, which have many openings, and 

 here, in the deeper parts, the nests, in which the 



