11 



jumps, and escaped. Rats were unable to climb up the inner 

 or outer corner of a concrete building. Three species — the 

 brown rat, the black rat and the roof rat (Mus alexandrinus) — 

 climbed a one-inch standpipe and a cocoanut tree with the 

 greatest ease.^ 



Rats have been observed climbing on elevator ropes and 

 cables to the upper stories of the highest buildings, and crossing 

 from building to building on telephone wires. Many authors 

 state that the brown rat is found mainly in the lower parts of 

 buildings and that the black rat and the roof rat seek the 

 upper floors. Nevertheless, black rats go into cellars and 

 brown rats almost always explore the attics of houses, especially 

 those which contain open water tanks; also they have been 

 found in the upper stories of some high buildings. 



RAT FOOD. 



Rats, like all rodents, are fitted to feed on vegetable matter, 

 grain, hard seeds, roots, nuts, etc., but in the course of time 

 they have become practically omnivorous, eating almost any- 

 thing edible, and gnawing many substances that have little or 

 no food value. 



RAT FECUNDITY. 



Possibly no mammal pest is more prolific than the rat. The 

 fabulous speed of its multiplication baffles all but the most 



efficient and determined attempts at extermination. Kolazy 

 says that he kept two female white rats in confinement that 

 produced twenty-six litters, or 180 young, within thirteen 

 months. Rodwell says that the female brown rat is believed 

 to bring forth from six to eight htters yearly; but estimating 



» Cred, Rieluird H., Public Health Reports, Vol. 28, No. 9, Feb. 28, 1913, pp. 382-38S. 



