HOUSE RATS AND MICE. 



11 



houses should be as cleanly 

 and as constantly inspected 

 as abbatoirs. 



Another important 

 source of rat food is found 

 in remnants of lunches left 

 by employees in factories, 

 stores, and public build- 

 ings. This food, which 

 alone is sufficient to attract 

 and sustain a small army 

 of rats, is commonly left 

 in waste baskets or other 

 open receptacles. Strictly 

 enforced rules requiring 

 all remnants of food to be 

 deposited in covered metal 

 vessels would make trap- 

 ping far more effective. 



Military trainino^ camps. 



^ ^ ^ ' B676M 



unless subjected to rigid Pig. S. — Guillotine trap made entirely of metal. 



discipline in the matter of disposal of garbage and waste, soon 

 become centers of rat infestation. Waste from camps, deposited in 

 covered metal cans and collected daily, should be removed far from 

 the camp itself and either burned or utilized in approved modern 

 ways. 



DESTROYING RATS AND MICE. 



The Biological Survey has made numerous laboratory and field 

 experiments with various agencies for destroying rats and mice. 

 The results form the chief basis for the following recommendations : 



TRAPS. 



Owing to their cunning, it is not always easy to clear rats from 

 premises by trapping; if food is abundant, it is impossible. A few 

 adults refuse to enter the most innocent-looking trap. And yet trap- 

 ping, if persistently followed, is one of the most effective Avays of 

 destroying the animals. 



Guillotine trap. — For general use the improved modern traps with a 

 wdre fall released by a baited trigger and driven by a coiled spring 

 have marked advantages over the old forms, and many of them may 

 be used at the same time. These traps, sometimes called guillotine " 

 traps, are of many designs, but the more simply constructed are pref- 

 erable. Probably those made entirely of metal are the best, as they 



