8 ANIMAL COMPETITORS 



Hessian soldiers, a queer echo of the London 

 idea that it came there with the Hanoverian 

 train of the present reigning house. By 1830 

 it had reached the Mississippi, and by 1857, 

 at least, was numerous in California." Now 

 no part of the country save the western deserts 

 is free from these pests ; and competent judges 

 estimate their numbers as at least five times 

 that of the human population, with which they 

 more than keep pace as widening civilization 

 more and more favors their support and in- 

 crease. 



Fecundity of the rat. A consequence is that 

 from time to time there is an overflow of rats 

 from one locality or region to another which 

 gives us a glimpse of the unseen crowd in the 

 midst of which we live. "In 1903, a multi- 

 tude of migrating rats spread over several 

 counties of western Illinois. They were no- 

 ticed especially in Mercer and Eock Island 

 counties. For several years prior to this in- 

 vasion no abnormal numbers were seen, and 

 their coming was remarkably sudden. An eye- 

 witness to the phenomenon informed the writer 



