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Jan., 1917 FURTHER NOTES ON THE WHITE-THROATED SWIFT The nests that have been taken were from three different localities, and nests have been observed in three others. Two seemingly ideal locations for the swifts, having the same characteristics as the others, have never been used either for nests or for roosting, and I am not able to offer any reason for this.

The fissures where nests have been located seem to be used only in the nesting season of May and June; during the balance of the year the birds congregate in large openings within rocks. The earliest and latest records I have for taking eggs are May 17 and June 13, respectively, both sets being fresh. The breeding season is so short that I am almost sure that but a single brood is raised. Incubation does not start until the set is complete.

During the heavy rains of January, 1916, quite a number of swifts were found on the ground in a helpless condition. It seems that some of the crevices had become flooded with water which had drenched the birds, causing them to attempt to escape, but it was impossible for them to fly with wet feathers. Several of these birds were kept in a warm place till their feathers were dry enough for them to fly away.

Observations are such as to fully convince me that these birds are residents here throughout the year. Many days often pass by during the fall and winter when no swifts are seen, and then at some unexpected time they appear in large numbers. The most common time of day for the swifts to be seen is the late afternoon, and when a swift can be located flying about, one is almost certain to soon see many more, except it be in the breeding season. They fly about in the vicinity of the crevices. where they make their homes and seem to have no fear of humans, hawks, or noise; yet, apparently as if at some signal, all the