BARN SWALLOW. 417 



as I have described is more than two pounds, but there is considerable 

 difference as to size between different nests, some being shorter by two or 

 three inches, and proportionally narrow at the top. These differences 

 depend much on the time the birds have to construct their tenement pre- 

 vious to depositing the eggs. Now and then I have seen some formed 

 at a late period, that were altogether destitute of the intermixture of grass 

 with the mud observed in the nest described above, which was a perfect 

 one, and had occupied the birds seven days in constructing it, during 

 "which period they laboured from sunrise until dusk, with an intermission 

 of several hours in the middle of the day. Within the shell of mud is a 

 bed, several inches thick, of slender grasses arranged in a circular form, 

 over which is placed a quantity of large soft feathers. I never saw one 

 of these nests in a chimney, nor have I ever heard of their occurring in 

 such situations, they being usually occupied by the American Swift, which 

 is a more powerful bird, and may perhaps prevent them from entering. 

 The eggs are from four to six, rather small and elongated, semitranslucent, 

 white, and sparingly spotted all over with reddish-brown. The period of 

 incubation is thirteen days, and both sexes sit, although not for the same 

 length of time, the female performing the greater part of the task. Each 

 provides the other with food on this occasion, and both rest at night beside 

 each other in the nest. In South Carolina, where a few breed, the nest is 

 formed in the beginning of April, and in Kentucky about the first of May. 

 When the young have attained a considerable size, the parents, who 

 feed them with much care and affection, roost in the nearest convenient 

 place. This species seldom raises more than two broods in the Southern 

 and Middle Districts, and never, I believe, more than one in Maine and 

 farther north. The little ones, when fully fledged, are enticed to fly by 

 their parents, who, shortly after their first essays, lead them to the sides 

 of fields, roads or rivers, where you may see them alight, often not 

 far from each otheu, on low walls, fence-stakes and rails, or the wither- 

 ed twigs or branches of some convenient tree, generally in the vicinity of 

 a place in which the old birds can easily procure food for them. As the 

 young improve in flying, they are often fed on the wing by the parent 

 birds. On such occasions, when the old and young birds meet, they both 

 rise obliquely in the air, and come close together, when the food is de- 

 livered in a moment, and they separate to continue their gambols. In 

 the evening the family retires to the breeding place, to which it usually 

 resorts until the period of their migration. 



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