ground on the trunks of oak trees, or performing gymnastic feats among the lowest branches. Although mentioned in Grinnell's list (not in Emerson's or Widmann's) this species is deemed rather rare by some of the valley people, and its appearance in numbers seems to indicate one of those waves that occasionally sweep over this country, of unknown origin or purpose.
The Mountain Chickadee (Penthestes gambeli gambeli) was another bird that appeared in numbers as the time for colder weather approached, and in similar manner was at first more frequently heard than seen, but later on was often noted feeding low down in friendly flocks with the nuthatches. One morning just such a combined flock was feeding along through the woods, as is its wont, when it came to a beautiful little glade whose sole avian occupant at the moment was a male hummingbird, probably Selasphorus rufus. One of the Mountain Chickadees worked its way from. branch to branch until it drew near the dead twig on which was perched the hummingbird, where upon it made a most vicious assault upon the innocent hummer and, not satisfied with driving it away from its own particular perch, kept returning to the attack every time its victim settled down again, repeating these assaults until finally the poor hummingbird left the glade in. disgust.
For noise and size the Northern Pileated Woodpecker (Phloeotomus Pileatus abieticola) is the most conspicuous bird in the valley. When one of these birds taps upon a dead limb it is no gentle imitation of a tap. It is the real thing! And when he calls he calls. Everybody in the neighborhood knows it, but he doesn't care. "No shooting allowed"—and he knows it. There is a tall pine tree with a dead top, just on the edge of Yosemite Village, which seemed to be a favorite point of vantage for a pair of these woodpeckers. They were often to be seen flying into or out of this tree or noticed chasing each other about its top, undisturbed by the people and automobiles below them, although one usually associates this bird with. dcep'woods uncontaminated by the presence of mankind. The description of this species given in the "Handbook of Birds of the Western United States" by Florence Merriam Bailey, is a good one, and very much to the point. There were several pairs in the valley, each of which seemed to have a favorite spot in the woods, and in or near which it might almost always be found snd even quietly approached to within a fairly close distance, close enough to notice many of the birds' habits, some of which seemed almost to take the form of antics—such as chasing each other about for no apparent reason, in a manner that looked very much like play. Yet this may, perhaps, have been the case of a young one pursuing its parent in the endeavor to induce it to produce some food. It was not always possible to distinguish between a full-grown youngster and an adult female, especially as this was in the moulting season.
A good example of this sort of thing was the case of a young Water-Ouzel (Cinclus mexicanus unicolor) which was seen one afternoon chasing its parent up the apparently perpendicular cliff of the upper Yosemite Falls—just where the fall would have been hsd the water supply kept up. In this case. the youngster, which seemed as large as the parent, was very persistent in its efforts, continually pursuing the older bird either by climbing or running along ledges, though occasionally taking to flight, and always begging for food. The parent kept dodging behind rocks snd into crevices, frequently turning and expostulating with the youngster whenever overtaken. This proceeding was kept up for a long time, until at last both birds got so far up the cliff as to be
