126 University of California Publications in Zoology. [Vol. 7 



Peromyscus sitkensis sitkensis Merriam. 

 Sitka White-footed Mouse. 



I took mice which I have referred to this species on Corona- 

 tion, Warren, and Duke islands, these scattered localities still 

 further emphasizing the peculiar distribution of the animal. (See 

 text figure 3, page 156.) Pour specimens were secured on Coro- 

 nation Island (nos. 8592-8595), two in abandoned mine build- 

 ings, one in an old shed in the woods, and one in a Microtus 

 runway. They were rather more numerous on Warren Island, 

 where nine were trapped (nos. 8596-8603, 9128), all in Microtus 

 runways. On Duke Island eighty traps produced three white- 

 footed mice in three nights (nos. 8604-8606). No other species 

 of Peromyscus was found on the islands where sitkensis occurs. 



Osgood (1909, p. 103) has referred two examples from For- 

 rester Island, Alaska, to P. s. prevostensis and possibly my speci- 

 mens might be considered as belonging to that race, but the 

 differences between the two forms are extremely slight, and the 

 specimens under consideration show so much variation that it 

 seems best to refer them to the stock form. They are smaller 

 than typical sitkensis from Baranof Island though no more so 

 than those from Chichagof Island. There are no appreciable 

 color differences in the series from the different islands. While 

 the skulls of some of my specimens show the somewhat elongated 

 posterior palatine foramina supposedly characteristic of prevos- 

 tensis, others are not differdht from typical sitkensis in this 

 respect. 



The specimens secured measure as follows : 



