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University of Calif orma Publications in Zoology V^ou 24 



weed-grown bottom lands, much more so than we found them to be on 

 any other wild land. At Flood Glacier we had diiSculty in getting 

 specimens, and at Great Glacier, though some small mammals were 

 more abundant than we found them elsewhere, only two white-footed 

 mice were obtained. At Sergief Island they were extremely scarce; 

 only one specimen was taken. 



borealis 



■macTorhinus 



Fig. S. Diagram showing individual and geographic variation in length of 

 tail of adult white-footed mice (both sexes). Figures at left of the vertical 

 lines indicate numbers of specimens measured; length of lines shows range of 

 individual variation; points connected by lines mark positions of averages. 



At the Junction, May 25 to June 6, all Peromyscus taken were 

 adult. Most of the females contained embryos, four or five in number ; 

 one or two were nursing young. At Telegraph Greek the first week 

 in June young mice began to get into the traps. From the third week 

 in June, on during the rest of the summer, the dark coated juvenals 

 formed the greater part of the catch. At Glenora two Peromyscus 

 were caught which had their cheeks filled with a mass of small seeds. 

 The cheeks were distended to the utmost, just as is so often seen in 



