318 Perry, Vesper Sparrow and Hermit Thrush. [jjj y 



excreta, ants and egg-shells just as the sparrows did. The female 

 did most of the brooding. Neither parent did much. The female 

 also did the greater part of the feeding. The food selected by the 

 parents for the young consisted entirely of insects either in the larval 

 or adult state. Katydids, grasshoppers, crickets, sawfly larvae, 

 robber flies, a few hairy caterpillars, and a moth or two made up 

 their food. I noticed such a variation in the gain in weight of the 

 different nestlings that I marked them on the head with paint in 

 such a way as to distinguish one from the other, so that I could 

 determine whether the parents fed impartially. Table II shows the 

 number of times, from August 7 until August 9, that each bird 

 was fed. 



Table II. 



FEEDING PERIOD. 



Each figure in the table gives number of feedings for each period. 



Each figure in the table gives number of feedings for each period. 

 The parents fed indiscriminately. Bird III did not receive as 

 many feedings as the others and therefore lost a greater amount in 

 weight. Bird II received the most feedings and his weight from 

 August 7 to 9 shows a gradual increase. Table III shows the share 

 each parent took in caring for the young in so far as I was able to 

 distinguish them. I could not distinguish them until the fifth 

 day. 



Their method of approaching and leaving their nest was like 

 that of the sparrows. The first few days neither parent gave a call 

 when approaching, and it was only by close watching that I could 

 tell that they had visited the nest. Often, however, they gave a 

 deep, throaty "Cluck" when on the nest's rim. Soon they began 

 to give a robin like "Chirp" or a "Neink, neink" call, when some 

 distance from the nest. This was taken by the bird on the nest as 

 a signal to leave. One day the male was having difficulty inducing 



