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 Sep., 9o I THE CONDOR 29 Nesting Habits of the Desert Sparrow Hawk Near Santa Monica, Cal. BY H. G. RISING, LOS ANGELES, CAL. N this locality the sycamore trees found in the mouths of the canyons leading back into the foothills have always been favorite nesting places for the Desert Sparrow Hawk (Faico spar- verius desertico[us.) These trees are many of them very large, and the nu- merous cavities and woodpeckers?. ex- cavations furnish ideal nesting sites for these birds. Although there are a good many oak trees among the sycamores the Sparrow Hawks do not nest in them, and during five years collecting in this locality I have not found a sin- gle set of their eggs in an oak tree. There is one fact in regard to the nesting of these birds which I have never found any one able to explain. This is, why the birds never have to abandon a set of eggs on account of water during wet seasons. I have so often had the bird refuse to leave the nest that I always climb to it whether the bird is flushed or not. I have many times found a nest filled with water, and I always feel in the water for eggs but have never found any. These rains often occur right in the height of the nesting season, sometimes filling nests from which I had already taken one set of eggs. It seems strange that the birds do not get caught in some of the leaky nests once in a while, but this does not seem to be the case. The nesting season here varies greatly, beginning as early as the sth of March in some years and in others not until the middle of' April. The duration seems to depend to a great ex- tent upon how many times the birds are robbed, as they will lay several sets if they are not allowed to hatch the eggs. 'This spring I started out with the intention of taking a series of Sparrow Hawks' eggs for Mr. G. Frean Morcom of Los Angeles. As usual I did all of my collecting near Santa Monica, with' the single exception of one trip up the beach to a canyon near Point Dumas, where I secured five sets of eggs. The remaining twenty-eight sets of this series all came from the same locality in which I have done most of my collect- ing, Santa Monica and vicinity. In making this series I used especial care with reference to keeping the eggs from each nest separate from those taken from other nests, so that the sev- eral sets taken from one nest during the season would constitute a series of itself. My intention was to watch the nests closely and to take each set laid as soon as it was complete, in order to find out how long the birds would keep on laying; but I was unfortunately obliged to stop collecting the last of May and so could not complete the ex- periment. [ took second and third sets from nests in several instances and in one case even got the fourth set. The intervals between the completion of the sets ranged from 20 to 26 days, with the exception of two, one of which  was 29 days while the other was 4 days. The following is a short record of a few of the nests from which I took sets this season. For the sake of conven- ience I refer to them as Nest No , No 2, etc. Nest No. i is a woodpecker's exca- vation in the dead stump of a sycamore tree, and is about I5 feet above the ground. The mouth of the opening has been broken open until the hole is about five inches wide by fourteen deep. I took the first set of five fresh eggs from this nest on March 24, the parent bird watching proceedings from a neighboring tree. The second set of five eggs, also perfectly fresh, was taken April i8, the bird being flushed before the nest was reached. The third set, consisting of four slightly in- cubated eggs, was taken May 9. A fourth set of two eggs, also slightly in- cubated, was taken on the 29th of May. On thee last two occasions the birds