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Bird - Lore 



while they were incubating and they had each time deserted the nest and built 

 a new one in the vicinity. Some of the deserted nests were empty, some con- 

 tained one or two eggs, and some the full complement of four, our only way of 

 knowing that the nests were deserted at the time of discovery being the finding 

 of another nest in the vicinity containing warm eggs. Usually we were unable 

 to discover the cause of desertion, but in two of the nests were the eggs of the 

 Cowbird. The eggs of the two species are almost identical and yet the Chat 

 seems to know the difference or to be able to count and remember the number 





A TAME CHESTNUT-SIDED WARBLER FEEDING ITS YOUNG 



which she has herself laid. I have known no instance of a Chat hatching out the 

 Cowbird's egg. 



A shy bird like this is very discouraging to the student of bird home-life 

 for, when the mere discovery of the nest causes the bird to desert, it gives him 

 not even a chance to test his skill. Upon two occasions, however, we were able 

 to outwit the Chat by discovering the nests from a distance and not going near 

 them until the proper time. One nest was located in an elm sprout close beside 

 a cow-path and the bird had apparently become accustomed to the passing of 

 the cattle. It was raining on the one day that we had a chance to photograph 

 this nest and this, perhaps, caused the bird to stick closer. I set up my umbrella 

 blind and my camera at a distance without disturbing her, and, getting inside, 



