i894.] 189 [Miller. 
Mr. Bolles found this mouse common at Chocorua in open or 
scantily wooded places, and near buildings. 
13. SiTOMYS AMERICANUS CANADENSIS Miller. 
The Canadian white-footed mouse occurs sparingly through- 
out the region explored on Mount Washington. Several were 
trapped under one of the barns on the summit, and we secured 
specimens in Great Gulf, the Alpine Garden, Tuckerman's 
Ravine, and near the Lake of the Clouds. These specimens are 
in every way typical of this strongly characterized race or species. 
We also took specimens at Profile Lake, and Mr. Bolles has 
found the animal at Chocorua. In both of these localities the 
mouse is strictly confined to dense woods. 
I have examined several hundred additional specimens of 
Sitomys of the americanus group since describing this form 
(Proc. biolog. soc. Wash., v. 8, p. 55, June 20,1893). This 
material in every way confirms the characters then brought 
forward, and makes me feel less inclined to treat the animal as a 
subspecies. Specimens intermediate between S. americanus and 
S. a. canadensis are of the utmost rarity, and, as I have already 
stated, do not occur in any particular region. 
A series of over one hundred skins of /Sitomys americanus arc- 
ticus received from Mr. Will C. Colt who took them at Osier, 
Saskatchewan, differ from S. americanus canadensis only in their 
grayer ears and much shorter, more strongly bicolored tails. Li 
the general color of the body the two forms are exactly alike. 
The ears of arcticus are, however, more liairy than those of ca7ia- 
densis, the whole peripheral internal portion being densely covered 
with short silvery white hairs. Externally the ears are silvery 
white, except a broad band running from the anterior base almost 
to the tip. This area is nearly black in strong contrast. This 
striking color pattern is not constant, but it occurs so frequently 
as to give a decided character to a large series of specimens. 
Only the faintest suggestion of such marking is to be seen in the 
ears of S. a. canadensis. In the most extreme examples of S. 
americanus arcticus the tail is very sharply bicolor, pure white 
ventrally and black dorsally ; the black dorsal stripe in strong 
contrast with the color of the animal's back. In other specimens 
this stripe shades to dark sepia, about as in the darkest-tailed 
individuals of S. americanus canadensis. Mr. Colt did not 
measure the total length of his specimens, so no direct conipar- 
