Feb., 1912. Mammals of Illinois and Wisconsin — Cory. 181 



hygienic point of view. The spread of the Bubonic Plague has been 

 proved to be due to them* and it can readily be understood how they 

 could easily become a source of contagion for other diseases as well. 

 To those who suffer from their depredations a publication of the U. S. 

 Department of Agriculture entitled ''How to destroy Rats," by D. E. 

 Lantz, (Farmers' Bulletin, No. 369, 1909) is recommended. In writing 

 of this species Dr. C. Hart Merriam says,t "He is not content with 

 deriving his sustenance at our expense; but to save himself the trouble 

 of a walk between meals, takes up his abode in or under our dwellings 

 and outhouses. In unsettled regions he often makes long journeys 

 from house to house, but I have never known him to make his home at 

 any great distance from buildings. 



"Rats are good swimmers, and in their migrations from place to 

 place (which are usually performed at night and thus escape notice) 

 they do not hesitate to swim rivers and ponds that lie in the way. 

 Though chiefly nocturnal, they are often seen in the daytime. They 

 are exceedingly prolific, commonly bringing forth from seven to twelve 

 young at a birth, and having several litters each season. Some idea 

 of the number of Rats inhabiting large cities may be had from the fact 

 that, at Paris, in a fortnight's time, more than six hundred thousand were 

 killed in the sewers. The skins were manufactured into kid gloves." 



Specimens examined from Illinois and Wisconsin: 

 Illinois — Chicago, 2; Fox Lake, 8 (6 in alcohol); (I. S. L.) Havana, 



I = II. 

 Wisconsin — Beaver Dam, Dodge Co., 2; (O.) Lake Geneva, 4 = 6. 



The following introduced species may occur in Illinois, but I find 



no satisfactory record of either having actually been taken in the state : 



Epimys rattus (Linn.). (Syst. Nat., X ed., I, 1758, p. 61.) Type 



locality — Sweden. A nearly cosmopolitan species introduced in 



North America at an early date. It was formerly common in many 



parts of' the United States, but since the advent of the Norway or 



Brown Rat, has become rare except in scattered localities. It has 



been recorded from Indiana, Tennessee, Kentucky and Iowa, and is 



claimed to have occurred in Illinois in early days. It has also been 



accredited to Wisconsin by Lapham and Strong ; but its occurrence 



in that state requires further confirmation. 



Epimys alexandrinus (Geoffrpy). (Descr. Egypt, II, 1818, p. 733.) 



Type locality — Egypt, Africa. This species has a much more south- 



* The Rat is very susceptible to the disease and a large number of the Rat fleas 

 examined in infected houses contained the Bacillus pestis in their stomachs and 

 mouths. 



t Mamm. Adirondack Reg., 1886, pp. 259-60. 



