62 Miller — Description of a Nciv White-Footed Mouse 



and body of a large male, 31 inches ; tail, 2 inches. In another 

 si)eciinen, the head and body oj^ inches; tail, 1 1 inches. In 

 spring the hairs of the upper ])arts are ]:)lumbeous at the base, 

 tipped with ashy and yellowish brown ; a few longer hairs, en- 

 tirely blacky interspersed. The tips of most of the hairs deepen 

 into black along the back, giving a ])road, black stripe when the 

 hair lies flat. In some specimens tliis stripe is not so dark as 

 in others, but is quite distinct in all, while in some it is pitch- 

 Ijlack." It will be remembered that one of the noticeable color 

 features of S. canadensis is the indistinctness of the dark dorsal 

 stripe; hence Mas bairdii, whatever it really may be, is a very 

 different species. 



The animal from P)Urlington,Vermont, described by Baird under 

 the name of Hesi')cromysmyoldcs (Gapper) (]\Iam. N. Am., 1857, p. 

 472), is, in part at least, the same as the subject of the present 

 paper. Baird remarks that " all the white-footed mice fro.u near 

 Burlington, Vermont, had much longer tails in jn-oportion than 

 those from Middleboro, Massachusetts." Tlie only specimens, 

 three in num1)er, that I have seen from the locality in question 

 are, however, typical amcricanns. Baird 's statement, " tail verte- 

 l)ra^ generalh^ .25 of an inch longer than head, and Ixxly with a de- 

 cided i)encil at the end," and also table of measurements on page 

 473, refer, without question, to the long tailed form ; but his descrip- 

 tion leaves a slight doubt as to just what animal he had in hand. 

 I have never seen a specimen of >S'. canadensis in which the color is 

 " more vivid yellowish brown " than in »S'. amcricanns, nor do 

 any resemble S. aureoliis in color, as is said to be the case with 

 "iiT. wyoides.^^ Baird considered the presence of cheek pouches 

 to l)e the best diagnostic character of myoides. INIore recently', 

 however, it has been shown by Allen (Bull. M. C. Z., I, 18G9, 

 229) that these structures occur also in the common ^S'. auieriran iifi. 

 It is worthy of remark, in this eonnection,that I have found the 

 cheek pouches of *S'. canadensis much the more frequently and 

 conspicuously distended with food. 



Sitomys americanus canadensis is exclusively a Canadian form, 

 replacing S. americanus in the spruce forests of New lU-unswick 

 (Restigouche county, E. A. Bangs; Northuml)crland county, G. 

 S. Miller), and extending south among the hills and mountains 

 at least to central New York and western Massachusetts. Sitomys 

 americanus is fL»und as far north as Digby, Nova Scotia, and Ivake 

 Simcoe, Ontario. Thus the ranges of the two forms overlap 



