258 



ECONOMIC ZOOLOGY 



Pocket gopher. Geomys bursarius, Fig. 164. This animal is found 

 in all of the states west of the Mississippi and in several of those east of 

 that river. It is very destructive to crops and trees and is often a 

 serious*pest. It also does serious damage by the mounds of dirt and 



PIG. 164. Mississippi Valley pocket gopher, Geomys bursarius. 

 Lantz, Directions for Destroying Pocket Gophers.) 



- (From 



stones which it throws out of its burrow, and by burrowing in the banks 

 it causes leaks in the irrigation canals. 



It may be destroyed by about the same methods that have been de- 

 scribed for pfne mice and ground squirrels, cooperation among adjoining 

 farmers being necessary to any great success. 



PIG. 165. Section of a portion of tunnels of a gopher colony, a, mounds of 

 loose soil; b, laterals leading to mounds, usually closed with earth; c, main runway, 

 usually clean. (From Lantz, Directions for Destroying Pocket Gophers.) 



Probably strychnia poisoning is the best method of extermination; 

 the same formulae may be used as given above for field mice; the bait 

 should be placed in the main runways, Fig. 165, c. Carbon bisulphid 



