W.B. Davis 1935. Elba, Cassia Co., Idaho, June 12, in the Canyon, one of which was collected. I saw several Mountain Chickadees in the willows along the creek up near the head of the canyon. It appears to me that the Mountain Chickadee ranges higher zonally than does the Long tailed Chickadee. I heard dozens of Ruby-crowned Kinglets singing in the tops of the Douglas Fir. I heard one Junco, but was unable to collect it. On the way back to camp I jumped a deer and a Mountain Lion. The latter was near the site where the deer had been bedded down and when frightened it trotted in long easy strides across the ridge and down into Cassia Creek Valley. It is reported - Mr. Wickel and others - that a few have given some trouble with the cattle the past few years. For the past two days I have been hunting squirrels here at Elba. Both O. bregmaeus and arnutus are here, and I believe are occupying the same type of habitat.