1909] The 1907 Alexander Alaska Expedition. 245 
THE MAMMALS. 
By EpmMuND HELLER. 
The present paper is based on the mammals obtained by the 
Alexander Expedition in southeastern Alaska during the sum- 
mer of 1907. The bulk of the material described in this paper 
was collected by Messrs. Frank Stephens, Joseph Dixon and 
Chase Littlejohn, who accompanied Miss Alexander. Most of 
Miss Alexander’s time was devoted to the collecting of the larger 
species, chiefly the Ursidae, which have been turned over to Dr. 
C. Hart Merriam for identification and description. 
The collection, excluding the bears, comprises some four hun- 
dred and sixty specimens in which twenty-one species are repre- 
sented. Special attention was given to Admiralty Island, which 
heads the list of islands with two hundred and fifteen specimens, 
comprising eleven species. Considerably less time was given to 
Baranof Island where but sixty-four specimens, representing 
seven species, were obtained. The Chichagof Island material 
consists of thirty-one specimens covering four species. On the 
adjacent mainland at Glacier Bay one hundred and fourteen 
specimens were obtained, in which lot but six species are in- 
cluded. Helm Bay on the Cleveland Peninsula, somewhat far- 
ther to the south, contributed twenty-five specimens and _ six 
species. Thomas Bay is represented by eight specimens and four 
species, and Etolin Island by two species, each represented by 
single specimens. 
The mammals known to inhabit the islands of southeastern 
Alaska are to a large degree widespread forms throughout the 
coast islands and the adjacent coast. This uniformity in distri- 
bution is apparently due to the narrowness of the dividing chan- 
nels and to the carrying agency of the large ice masses recently 
so prevalent in the region. The great depth of the channels 
which separates many of the islands from their neighbors gives 
them the marks of considerable age. This age factor alone would 
