_Description._--Size medium; back from near Clay Color to near Cinnamon-Buff with admixture of black hair usually forming a dorsal band; sides from near Clay Color to near Cinnamon-Buff and lighter than back; lateral line usually distinct, and clear Cinnamon-Buff; belly white, sometimes with slight suffusion of Cinnamon-Buff mid-ventrally; tail bicolored, brownish to brownish-black above, grayish-white to yellowish-white below; ears dark, sometimes flecked with color of the sides, edged with Cinnamon-Buff; feet grayish-white above; auditory bullae large, relatively broad and flat; incisive foramina relatively short and narrow, widest posteriorly; zygomata not widely bowed outward; mastoid region relatively wide; frontal region well inflated; nasals relatively narrow, short, and parallel sided. _Comparisons._--From _Zapus hudsonius hudsonius_, _Z. h. canadensis_ differs as follows: Upper parts generally dull averaging lighter, less black tipped hair; sides also lighter with less suffusion of dark hair; frontal region more inflated; mastoid region averaging broader; auditory bullae broader; distance from incisors to postpalatal notch averaging slightly longer. For comparison with _Zapus hudsonius acadicus_, _Zapus hudsonius ladas_, and _Zapus hudsonius americanus_ see accounts of those subspecies. _Remarks._--Bole and Moulthrop (1942:165) refer 2 specimens from Elba, New York, to _Z. h. hardyi_ (= _acadicus_); they are more nearly like _Z. h. canadensis_ in size and shape of the auditory bullae and general color of the pelage. A specimen from Spectacle Pond, New York, has the narrow pterygoid fossae and relatively narrow auditory bullae of _Z. h. acadicus_ and the relatively short, narrow incisive foramina, inflated frontal region, and color of _Z. h. canadensis_ to which the specimen is here referred. Intergradation is noted also in animals from Schreiber, Ontario. They resemble _Zapus hudsonius hudsonius_ in their darker coloration and shape of auditory bullae but in the remainder of the characters studied resemble _Z. h. canadensis_ to which they are referred. Specimens from Notre Dame de la Dore and 1/2 mi. N Mistassini Post, Quebec, in size and shape of the auditory bullae and in width of the pterygoid fossae, closely approach _Z. h. ladas_ but in color, distinct dorsal band, and in narrower zygomata are all nearest _Z. h. canadensis_ to which subspecies they are here referred.