In physical conformation, cross foxes are identical to red foxes, though according to Teancum's Mammals of Utah (1922), they may be slightly larger with a bushier tail and with more wool under the feet. The cross fox derives its name from the vertical dark band running down the back, which is intersected with another horizontal band across the shoulders. The back and sides are yellowish rufous, which is more vivid on the flanks and the sides of the neck. Excepting the muzzle, the upper part of the head, the hind quarters and the outsides of the shoulders and thighs have dusky brown underfur and black outerfur. The flanks and sides of the neck are reddish yellow, while the muzzle, ears and underparts of the leg are black. The long hairs of the tail are greyish or yellowish red with black tips, though the tip of the tail is always white. They are distinguished from "bastard" foxes (which are usually the result of a red/silver fox mating) by the dorsal stripe which is black rather than dark red.