54 AX ECONOMIC STUDY OF FIELD MICE. 
REPRESSION OF FIELD MICE— ACTIVE MEASURES. 
We pass now to a consideration of such means for the repression 
of voles as are under the immediate control of the farmer. Thesj 
consist of trapping and other mechanical methods of destruction and 
the use of poisons, fumes, and micro-organisms. 
TRAPPING. 
Trapping is a simple way to destroy iield mice, but it is seldom 
resorted to because few people have patience to follow it up perl 
Fig. '2. — Field mouse caught in hailed guillotine trap. 
sistently and to look after the necessary large number of traps. 
When field mice are abundant it is essential to use many traps and to 
continue trapping for several weeks. Equipped with a hundred or 
Fig. 
-Field mouse caught in unbaited guillotine trap. 
more effective traps, a good trapper should be able to make decided 
inroads upon the numbers of the pests, if not to practically extermi- 
nate them over a limited area. 
