ECOLOGY OF NORTHERN MICHIGAN. 133 



11. My Otis lucifugus (LeConte). Little Brown Bat. I. One specimen 

 •was taken, September 1, by Peet. Wood reports seeing a bat on wing 

 August 22. These were the only bats seen on the island. 



No specimens of the Red-backed Mouse, (Evotomys gapperi), were taken 

 although they have been reported from Isle Royale by Coues (Mong. N. 

 American Rodentia, p. 145). Of special interest to the* student of the Isle 

 Royale fauna is Miller's "Notes on the Mammals of Ontario," (Pro. Bost. 

 Soc. Nat. His., 1897, Vol. 28, pp. 1-44). 



This collection from Isle Royale, although a small one, is of interest in 

 several respects. The Isle, it should be remembered, is 45 miles long with 

 a maximum width of 8^ miles, and is about 15 miles from the Canadian 

 shore. As might be anticipated, the affinities of the mammal fauna are 

 with those of the north shore of Lake Superior rather than with those of the 

 south shore. This is shown by the occurrence of the Caribou, Red Squirrel, 

 Varying Hare and, perhaps, the White-footed Mouse. 



It should also be borne in mind the relatively recent or postglacial origin 

 of this island fauna. Since the advent of the present fauna we have no 

 reason to believe that this island has ever been connected with the mainland. 

 In other words, the fauna and flora must have reached their present 

 location through the agency of winds, waves, lake currents, over the ice, and, 

 possibly, in the case of some forms, through the influence of man. 



