48 THE CONDOR Vol. XI eggs. barelv commenced in incubation, ?vas taken. In two instances a period of four days elapsed bet?veen the laying of the first and the second egg, incubation starting ?vith the deposit of the first egg. In five instances three eggs, and in every other case t?vo, were a complete set. This pair of birds ?vouK1 inva. riably deposit a second set, and eveu a third, xvithin twenty-one days from the time the first set ?vas disturbed. During the wet seasons of x9o7, I9o8 and x9o9 three eggs were laid, possibly indicating that the birds ?vere finding food more plentiful than formerly. For the past several years I have b&en observing these birds. hoping that some time they would select a site where closer observation of their nesting habits ?vou!d be possible. For the season of I912 they chose a site ?vhich was on 'a cliff-face overlooking a deep and narro?v canyon. From the opposite ?vall of this canyon the sitting bird could be observed, but ?vas too far a?vay for photo- graphic purposes. In this nest t?vo lusty youngsters ?vere reared. For some Fig. 17. VIE?,v FROM NESTING SITE OF PACIFIC HORNED Ow? ?EAR ESCOI?DIDO, CALIFORI?IA reason, best known to themselves, the birds left this site at the beginning of the present season, and set up housekeeping about three hundred feet below, in the same ganyon, in the most accessible place they had yet used. Here, on the 2nd of February, we located the nest by flushing the bird, after two hours of hither- to fruitless search for her. She had selected a ledge in a large rock pile overlooking the canyon and valley belo;v. The t;vo eggs the nest contained appeared to be fresh. This nest
- vas visited at intervals of once a xveek for the next four weeks, and in every in-
stance one bird flushed from the nest just as I ;vas climbing up over the big rock adjacent, its mate leaving its perch in a small oak tree farther down the hillside xvhen I was yet some distance a;vay. The bird leaving the nest xvould alight on sonre nearby rock, and ruffling up its feathers, let out a cat-call or txvo, but seemed little disturbed by my intrusion. and ;vould immediately resume incuba-
