I 
DICE — MAMMALS OF ALASKA 23 
Lutra canadensis canadensis (Schreber). Canada Otter. — Several were 
trapped by Indians in the winter of 1911 on Sullivan Creek near Tanana. Otters 
were reported to be common at the heads of the Tozi and Melozi. In March and 
April, 1912, trails and slides were common along the North Fork of the Kuskok- 
wim near its head. The trails led from the water-holes of the river to the snow- 
covered river-bars, and also into willow thickets and into the adj acent white 
spruce-paper birch forest. One was seen swimming in the Kuskokwim near 
Big River on July 13. The species is reported to occur commonly on the Bering 
Sea tundra near Bethel. A male trapped at the head of the North Fork of the 
Kuskokwim April 7, 1912, was very fat and weighed 13 pounds. 
Lynx canadensis Kerr. Canada Lynx.— A few tracks were noted near Tanana, 
along the Cosna River, and near the head of the North Fork of the Kuskokwim. 
Its trails were found in willows along the streams and in white spruce-paper 
birch forest. In walking in soft snow it apparently tries to step each time in its 
previous tracks. This habit is sometimes taken advantage of by trappers, who 
place a trap under one of the tracks. 
Synaptomys dalli Merriam. Dali Lemming-Vole. — One was taken in scrub 
willows at the bottom of a small valley 10 miles north of Tanana December 2, 
1911. Another was taken July 4, 1912, from the runway of a Drummond vole in 
horsetails near a lake at the junction of the McKinley Fork with the Kuskokwim. 
Lemmus yukonensis Merriam. Yukon Lemming. — Two young were taken June 
12, 1912, in grass mostly of the tussock type, at the border of a small lake near the 
head of the North Fork of the Kuskokwim. Continued trapping in the region 
failed to secure any more specimens. 
Evotomys dawsoni dawsoni Merriam. Dawson Red-backed Vole. — The naost 
abundant mammal of interior Alaska. It was taken in equisetum, sedges, and 
grassy areas about lakes; in nigger-heads; in willows and alders, both in the larger 
valleys and at timber-line; in paper-birch forest, white spruce forest, and black 
spruce forest; in growths of blueberries and dwarf birch, both in the valleys and 
above timber-line; on the high ridges above timber-line in sphagnum, grass, and 
low brush ; in cabins and caches in the woods ; and in burned timber. It was found 
most abundantly under shrubs in the black spruce forest. Specimens were pre- 
served from Fairbanks, Tanana, Mount Sischu, and Takotna; and on the North 
Fork of the Kuskokwim from near the head of the stream, from the junction 
with the McKinley Fork, and from near the East Fork. At Bethel one was taken 
at the border of the tundra in a tent pitched at the edge of a slough. 
This mouse makes short runways under logs and low bushes, but in general its 
runways are not well defined, for it does much traveling without following a defi- 
nite path. It has also been taken in the runways of the Drummond vole. In the 
winter it, as well as the other voles and the shrews, pushes its way at the surface 
of the ground through the very light snow. These burrows may be used only 
once, as shown by the tracks, or they may be traveled enough to form runways. 
Mice and shrews also sometimes come to the surface to travel, especially when 
the snow is crusted. Red-backed voles cause some inconvenience to trappers by 
feeding on stored food, by eating bait, and sometimes by springing the traps set 
for marten or mink. A female taken at the head of the North Fork of the Kus- 
kokwim May 21, 1912, contained four embryos each about 10 mm. in length; and 
one taken May 27 showed recent birth of young. One taken above timber-line 
