2 mi. S Melba, Canyon Co., Idaho, May 29, out of the kind of habitat in which we found it at Murphy and was in some high Artemisia tridentata along an irrigation ditch. I could find no burrows and I believe the animal must have wandered down there from the Atriplex only a short distance away and in which there were a few burrows. It made no sound at all, but merely hid in the underbrush through which I had to shoot to collect it. When I got back to camp I compared this squirrel in the flesh with several C. idahoensis which Twining had collected, and find them distinct. C. leurodon has yellow teeth, idahoensis white, the size is about the same; idahoensis has a bushier tail tinged with rufous underneath, leurodon lacks the bushiness of the tail and the rufous color underneath. However, there is a tinge of cinnamon on the under side of tail in leurodon as both the tail and the hind foot are smaller; the nose pad is about 1/3 as wide; the front and hind feet are whitish save for a rusty colored blotch; the claws of the front feet are stenderer and more curved;