322 University of California Publications in Zoology  \Vou. 24

Lack of suitable open country elsewhere may be an element in the
occurrence of a horned lark and a Savannah sparrow as Alpine-Arctic
species in this region, but the other species listed are all representative
inhabitants of the Alpine-Arctie Zone.

Results of this classification of the birds by their zonal predilections
may be summarized as follows: that the valleys of the upper Skeena
region, east of the coast ranges, are in the Canadian life zone; that on
the surrounding mountains there is a well defined belt of Hudsonian
Zone ; and that the treeless mountain tops pertain to the Alpine-Arctic
Zone. At this latitude the Canadian life zone does not reach the coast,
where but two life zones can be defined, Hudsonian from sea level
upward to the tree limit, and Alpine-Arctic above that.

An analysis of the occurrence of mammals in this general region,
as far as our more limited knowledge of them extends, tends to
corroborate the above statements based upon the avifauna.

The upper Skeena Valley is the northern limit reached in this
region by the following species of birds:

Phloeotomus p. picinus Bombycilla cedrorum
Tyrannus tyrannus Vireosylva olivacea
Hesperiphona v. brooksi Dendroica a. auduboni
Zonotrichia albicollis Dendroica magnolia
Junco o. shufeldti Dumetella carolinensis
Stelgidopteryx serripennis Troglodytes a. parkmani

Some of these get no farther north than the town of Hazelton. Of
the others, it is doubtful if favorable conditions occur for more than
fifty or sixty miles north of that point, at the outside. There are
enough of these southern species to give character to the avifauna of
this region, they all are stopped at practically the same boundary, and
some have closely related congeners in the country immediately to
the northward (see Swarth, 1922, p. 152).

Besides the species of mammals collected, certain others came to
our attention. Tracks of black bear (Ursus americanus) appeared
along the rivers in September when the salmon were dying. Coyotes
(Canis), though never seen, were frequently heard howling in Kispiox
Valley. Beaver (Castor canadensis) were actively at work in certain
small lakes near our Kispiox Valley camp. Fresh tracks of deer
(Odocoileus) were noted at the summit of Nine-mile Mountain, and a
single deer was seen in Kispiox Valley, September 8. A number of
shed horns of caribou (Rangifer) were found on Nine-mile Mountain,
but the animals themselves were not there at that time.