MAMMALS IN THEIR RELATION TO SPOTTED FEVER. 



19 



than the other meadow mice. In Avinter tliey are active under tlie 

 deep snow. 



MUSKRAT. 



{ Fiber zihethicus o,soi/oos('ns;is.) 



^Inskrats were formerly common in most of the sloughs and ponds 

 in the valley, but the extremely high price paid recently for their 

 pelts has led to a great reduction in their numbers. One was shot, 

 but no ticks were found on it. Their aquatic _ 

 habits may exempt them from such pests. 



BEAVER. 



( Castor canadensis. ) 



Beavers occur in the Bitterroot Kiver and 

 on Lo Lo aixl other creeks, but the}^ are very 

 scarce. Xone were examined, but it seems im- 

 probable that they would be attacked by ticks. 



POCKET GOPHERS. 

 {Tliomomijs fiiscus.) 



Pocket gophers are common over most of 

 the valley and in mountain parks and mea- 

 dows. Specimens were taken on Ambrose 

 Creek and west of Florence, but no ticks were 

 found on any of those examined. They prob- 

 ably do not serve as an important host for the 

 fever tick, as their lives are spent almost 

 entirely underground. Still ticks are occa- 

 sionally found on gophers in other localities. 

 Pocket gophers do considerable damage to 

 crops, especially to garden vegetables, or- 

 chards, and nurseries, but are easily poisoned 

 or trapped. 



JU3IPIXG MOUSE. 

 (Zapus prince ps.) 



Fig. 10. — Pocket gopher 

 (Thomomys fusciis). 

 (About i natural size.) 



The jumping mouse occurs in suitable 

 places throughout the valley and lower parts 

 of the adjacent mountains. Only a dozen specimens were secured, 

 and although none of them had ticks on them, it is probable that 

 they sometimes serve as hosts for nymphs or seeds. Unlike other 

 mice in the valley, they hibernate in winter, denning up with the first 

 hard frosts. They live mainly upon seeds of grass and other plants, 

 and are fond of rolled oats and au}^ of the small grains. 



[Cir. 82] 



