8 THE CONDOR Vol. XIX
birds will suddenly return to the fissures in the rock, and there seems to be nothing that will cause them to leave their selected roosting cavities. In the district lying within four miles around Slover Mountain I have never seen the swifts more than one mile distant from it.
During the extremely cold wave of early January, 1913, eight, to me perfectly healthy, swifts were taken out of a crevice where they, with many others, seemed to be roosting in a dazed or numb state. They were kept in a room for about six hours and then turned loose, one at a time, a few hundred feet from the point where they were captured. All flew away in a dazed fashion and nearer the ground than usual and none were observed to return to the place where they were captured. I had hitherto thought that they were numb from the cold, or possibly from the jar of a blast in their immediate vicinity; but it has been suggested to me that possibly they were hibernating. This raises a very interesting question, as it seems possible that these birds have intermittent hibernation periods. The facts are that these birds are not observed for many days in the coldest weather, yet are found to be plentiful within the rocks, in a dormant state.
It is claimed by some that these birds do not use their wings in unison, but I am of the opinion that they do flap both wings at the same time, at least part of the time if not always. When flying about feeding upon insects, usually at several hundred feet elevation above the ground, they make a few rapid beats with the wings, then soar a little while, then beat their wings rapidly for a few moments and so on. They vary the flight by sharp darts in other directions, probably to catch insects. When returning to the cliffs they often keep their wings beating fairly steadily. Both when penetrating and leaving the crevices they seem to use both their wings and feet as aids to locomotion.
Set no. 3 was donated to the United States National Museum (Accession 60163), where it proved the first set of eggs of this species in that institution. Set no. 5 was donated to the American Museum of Natural History where there had been no eggs of the White-throated Swift previously. Set no. 4 was donated to the California Museum of Vertebrate Zoology (now no. 1632 of the oological collection there).
Colton, California, November 14, 1916.
THE HUMID COAST of the Northwest appeals to the imagination of the worker from the arid interior not only because of its phenomenal forest growth—its bearded giants towering from one to two hundred feet above an almost impenetrable jungle—but because of the ornithological antitheses that result from the juxtaposition of ocean and forested mountains in northern latitudes.
On Tillamook Bay in northwestern Oregon, reached from Portland by winding down through the Coast Mountains with their lofty conifers and their canyon streams frequented by Water Ouzels, the shore that is strewn with the trunks of headless giants is so close beset by the living forest that the bird stu-
