William Clark, History of the Expedition Under the Command of Captains Lewis and Clark…
“ The small gray squirrel is common to every part of the Rocky mountains where timber abounds. He differs from the dark brown squirrel in colour only. The back sides, neck, head, tail and outer side of the legs, are of a brownish lead-coloured gray: the tail is slightly touched with a dark reddish colour, near the extremity of some of the hairs: the throat, breast, belly, and inner parts of the legs, are of the colour of a tanners’ ooze, and have a narrow strip of black, commencing behind each shoulder, and entering longitudinally about three inches, between the colours of the sides and belly. ”
