150 University of California Publications in Zoology [Vou.30

Neotoma cinerea saxamans Osgood. Northern Bushy-tailed Wood Rat

Three specimens collected (nos. 34432-34434), one at Atlin and two
at our camp on lower Otter Creek. In this region, as elsewhere in the
northwest, the wood rat is more or less of a pest, invading cabins and
destroying or carrying away almost anything that can be moved. We
saw slight trace of the presence of this species, however, and it seems
likely that the wood rats had suffered temporary reduction of numbers
together with other small rodents. :

Synaptomys borealis dalli Merriam. Dall Lemming Mouse
One specimen (no. 34435), a young male, was trapped on upper
Otter Creek (3800 feet altitude), on July 30. The species was not
otherwise encountered.

Microtus drummondii (Audubon and Bachman)
Drummond Meadow Mouse
Fourteen specimens were preserved (nos. 34436-34449), thirteen
from the vicinity of Atlin and one from the summit of Spruce
Mountain (5000 feet altitude). They were rare, one specimen in two
or three nights being the most to be hoped for in a line of twenty-five
or thirty traps.

Microtus mordax mordax (Merriam). Cantankerous Meadow Mouse

Nine specimens were collected (nos. 34450-34458), four from Atlin,
four from Otter Creek (3000 to 4000 feet altitude), and one from
near the summit of Spruce Mountain (5000 feet altitude). These nine
specimens represent approximately the result of eighty traps set out
for two weeks. Not that just that number of traps was set for exactly
that number of days at any one period, but that would be about the
sum total from traps placed where Microtus should have been trapped.
Two pregnant females contained three and four embryos, respectively.
In an extensive series from the upper Stikine River, trapped when the
animals were abundant, the number of embryos was usually five or
six.

Ondatra zibethica spatulata (Osgood). Northwestern Muskrat
Muskrats were seen at various times in ponds at the edge of the
town of Atlin, and elsewhere in suitable places east to Lake Teslin.
"The species is abundant throughout this whole region.