10 



COMMON MAMMALS OK W KSIT.H N MONTANA. 



proprietary squirrel poison al a nel cos! of 28 cents a pound. In 

 (his bulletin a much more ell'ective preparation costing not more than 

 12 or l.~> cents a pound is recommended. Another advantage of co- 

 operation is in the purchase of material at wholesale prices. Thus, 

 while drug stores retail strychnine at from $1.50 to $2 an ounce, it 

 may be bought in quantities of 5 ounces or more at from GO to 65 

 cents an ounce. 



It is recommended therefore that, whenever possible, standard poi- 

 sons be mixed in quantity by State experiment stations, counties, com- 

 mercial clubs, granges, or other associations and then distributed at 

 cost price to the large number of individuals who would thus be in- 



ITlO. 2. — Columbian ground Sflulrrel. 



duced to use them. In the Bitterroot Valley a part of the spotted- 

 fever fund appropriated by the State might well be used for this 

 purpose. 



COLUMBIAN GROUND SQUIRRELS. 



DISTRIBUTION. 



The Columbian ground squirrel (fig. 2), known also as picket pin 

 and gopher, is by far the most important rodent in western Montana 

 in its relations both to agriculture and to spotted fever. It occurs 

 also in northern Idaho, northeastern Oregon, eastern Washington, 

 and the mountains of southwestern Alberta and southeastern British 

 Columbia. 



AS TICK HOSTS. 



The Columbian ground squirrel is undoubtedly the most impor- 

 tant host of the two younger stages of the fever tick, and is almost 



484 



