Notes on Cliff Swallows 



151 



times one of the l)irds would remain in the nest during the process, to help 

 in molding. From this base a side would be built to the roof, and then the 

 remaining space was filled in to leave an opening at the top. None of the nests 

 in this colony had "necks." The great majority of the openings were on a 

 line with the middle of the nests. The nests were thinly lined with dry grass. 



Building was done irregularly, and, to us, without rhyme or reason as to 

 hour of day or amount of work done — sometimes at 5 a.m., at other times in 

 the afternoon and evening; on June i, all day. One pair completed the upper 

 half of their nest on this day, l)ut this was evidently too (|uick work, as the 

 nest soon fell off. 



Usually, after a few hours of work there would be a long time of feeding 

 or play. 



The colony contained one group of four nests and three groups of three, 

 all the others were single. 



Birds were not raised in all the nests finished on the north side; some fell 

 off, and the English Sparrows alluded to above destroyed another group of 

 three on this side. Broken Sparrow eggs were found in the debris of both 

 groups destroyed by them. After their second failure they left the vicinity. 



Mating took place toward the end of May, usually while the birds were 

 gathering mud. The first young birds were hatched about June 12, the last 

 on July 3. The young birds were fed by both parents, and very frequently. 

 At first the birds entered the nests with the food, but after about a week the 

 bills of the little birds were pushed out to receive the food, the old bird cling- 

 ing to the outside of the nest and bracing itself with its tail. A few days later, 

 the whole head appeared at feeding. After the young birds had left the nest, 

 we sometimes saw the feeding take place on the wing. 



While the birds were small, the parent dropped the excrement from the 

 edge of the nest; but, later on, the young bird voided it from the nest. 



