244 ECONOMIC ZOOLOGY 



period be offered a much greater activity will probably be secured from 

 both individuals and from clubs and societies organized for the specific 

 purpose of waging war upon this, our most destructive pest. 



Lantz (170) gives the following summary of the measures needed 

 for combating the rat and mouse nuisance: 



"i. The requirement that all new buildings erected shall be made rat- 

 proof under competent inspection. 



"2. That all existing rat-proof buildings shall be closed against rats and 

 mice by having all openings accessible to the animals, from foundation to 

 roof, closed or screened by door, window, grating, or meshed wire netting. 



"3. That all buildings not of rat-proof construction shall be made so by 

 remodeling, by the use of materials that may not be pierced by rats, or by 

 elevation. 



"4. The protection of our native hawks, owls, and smaller predatory 

 mammals the natural enemies of rats. 



"5. Greater cleanliness about markets, grocery stores, warehouses, 

 courts, alleys, stables, and vacant lots in cities and villages, and like care on 

 farms and suburban premises. This includes the storage of waste and 

 garbage in tightly covered vessels and the prompt disposal of it each day. 



"6. Care in the construction of drains and sewers, so as not to provide 

 entrance and retreat for rats. Old brick sewers in cities should be replaced 

 by concrete or tile. 



"7. The early threshing and marketing of grains on farms, so that stacks 

 and mows shall not furnish harborage and food for rats. 



"8. Removal of outlying straw stacks and piles of trash or lumber that 

 harbor rats in fields and vacant lots. 



"9. The keeping of provisions, seed grain, and food-stuffs in rat-proof 

 containers. 



"10. Keeping effective rat dogs, especially on farms and in city ware- 

 houses. 



" ii. The systematic destruction of rats, whenever and wherever possible, 

 by (a) trapping, (6) poisoning, and (c) organized hunts. 



" 12. The organization of clubs and other societies for systematic warfare 

 against rats." 



Mice. Closely related to the rats and associated with them in the 

 minds of all as plagues of mankind, are the various species of mice 

 of which two or three will be noted here. The most familiar of these 

 is the common house mouse, Mus musculus, a pest not only about 

 houses and barns but also in the fields. Like the rats, this mouse is 



