PRAIRIE-DOGS 153 



Whether the disease has been exterminated 

 among these wild rodents, remains to be seen. 

 The fact that the Beechey ground-squirrels 

 have shown themselves receptive to the fleas 

 which are peculiar to brown rats, and to the 

 disease, led to observations and experiments as 

 to other rodents. It is found that rock-squir- 

 rels are quite readily infected, mice and 

 pouched gophers less so, but wood-rats and 

 prairie-dogs succumbed at once. There seems 

 no reason to suppose that any rodent may not 

 carry the fleas about in its fur a short time, if 

 not permanently; or that any rodent is immune 

 against the plague if punctured by an infected 

 flea. A ray of light is shed upon this dark as- 

 pect of the case by the announcement that along 

 with the fleas goes a small staphylinid beetle 

 which exists as a parasite on both rats and 

 squirrels, and feeds ravenously on the fleas. 



Importance of the prairie-dog. But of all 

 the ground-squirrels none equals the prairie- 

 dog in interest or importance. 



It is a denizen of the dry plains east of 

 the Rockies, while two or three other species 

 inhabit the mountains, the Utah basin, and 



