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 In the Spartina with the Swallows 119 August and early September: but, as their number decreases, that of the Whitebreasts hicreases, reaching the height at the time the Eaves depart. In summer the roost belongs almost entirely to the Eaves, who flock here from the surrounding country. So do the Roughwings. a few hundred only, and some Barn Swallows and Whitebreasts, which two species are not numerous breeders in this region. As soon as migration begins, about the middle of August, the TREE OR WHITEBREASTED SWALLOWS Immature liirds on the ground gathering nesting material, which they drop after carrying a short distance, thus apparently giving a premature exhibition of the nest-building instinct Piicto^raphed from nature by Frank M, Chapman, Leonia, N- J,, August, 1897 Eaves are greatly reinforced, and for the next four weeks enormous numbers are present, but it is probable that they are not always the same individuals, as their numbers vary from day to day. It seems they perform their migrations b}' stages, from roost to roost, employ- ing mainly the first hour of the morning for their flights, spending the day resting and feeding in the region surrounding the roost. The substitution of arriving Whitebreasts for departing Eaves is in the beginning almost imperceptible, but at last we see that the one has taken the place of the other entirely. The Roughwings become