1909. June 8. Cofey 4 Lake Umbagog. When I first visited my boat house on June 3 the Have Swallows were only beginning the foundation of their nests. On the 6th none of the nests were more than one half built. Today a dozen or more are apparently completed, at least externally. This morning as I was watching the birds I saw two come together in the air and whirl around and around straight down to the ground, where they remained for more than a minute, in what I took to be sexual union, waving and fluttering their wings like butterflies. The other members of the colony seemed actively interested in the affair, and indeed not a little excited by it, for they collected over the prostrate birds and dashed down almost to them, with loud cries. When the pair finally separated, one bird flew off in one direction and the other in another. I do not think it could have been a fight, for Have Swallows are among the most all peaceable and social of birds and I have never known them show the slightest tendency to quarrel. Moreover I have seen Swifts copulate in precisely the same manner, although they do not often, if ever, remain so long on the ground together. The Swallows in this colony do not seem to be in the least disturbed by the dozen or more Bronzed- Grackles which are nesting in some balsams that practically shade the boat house; nor do they pay the least attention to the Broad-winged Hawks which the Grackles mob every time they appear near the island. Eave Swallows. Sexual Contact in mid air. Unfriendly turns mit Crow Black birds and Broad wing Hawks, 28