252 University of California Publications in Zoology. (Vous 
Survey collection from Vancouver Island, British Columbia, 
Washineton, Oregon, and California, show only trivial differ- 
ences upon comparison with the material from southeastern 
Alaska. Skulls from Washington and California exceed in size 
and massiveness the largest from southeastern Alaska. The two 
adult skulls from Admiralty Island have a very small inter- 
orbital width, considerably less than a third of the mastoid 
width. Six specimens are in the collection, all of which are 
males, three of them adult. Four of these were secured in the 
central part of the island, at Hasselborg Lake, and one each from 
Mole Harbor and Pleasant Bay. 
MEASUREMENTS.—Type: total length, 1030; tail vertebrae, 
485; hind foot, 175; length of sealed part of tail, 147; width of 
sealed part of tail, 132. Average of three adults: total length, 
1035; tail vertebrae, 480; hind foot, 177; leneth of sealed part 
of tail, 262; width of sealed part of tail, 124. Skull (type): 
Hensel, 115.5; zygomatic breadth, 22.5; mastoid width, 72; inter- 
orbital width, 22.5; leneth of nasals, 50.5; width of nasals, 23. 
The only other adult skull has the following dimensions: Hen- 
sel, 117; zygomatic breadth, 97; mastoid width, 74; interorbital 
width, 21; length of nasals, 52; width of nasals, 22.5. 
Dixon has the following notes on the beavers observed about 
the lakes in the interior of Admiralty Island: 
‘““We were very pleasantly surprised to find beavers on Ad- 
miralty Island, as we had been told that there were none on any 
of the islands between Sitka and Juneau. The lakes with their 
irregular shore line and quiet little bays were the natural home 
of the beavers and they had lived there in peace and seclusion 
for many years. At intervals of four or five years, the In- 
dians who owned the region by tribal inheritance were accus- 
tomed to visit the lakes in the early spring and trap for beavers. 
But the Indian methods of trapping were crude and they quar- 
reled among themselves so they did not catch many beavers. 
Aside from this we saw only one thing that would lead us to 
think that the beavers were ever bothered. This was a beaver 
house that had been torn open by a bear. 
“At the time of our visit many of the younger beavers had 
never seen a man and regarded the canoe with shy curiosity; 
