THE FOOD OF NESTLING BIRDS. 289 



tarian birds, with the exception of the pigeons and the 

 doves, feed their young for a time on soft-bodied insects. 

 The crow blackbird, which in the adult stage is both 

 insectivorous and a seed-eater, feeds its young on. soft, 

 plump spiders, young grasshoppers, and small cutworms. 

 The pigeons feed their young on pigeons' milk, which is 

 grain in semi-fluid condition, partially digested in the 

 parent's crop and fed to the young bird by regurgitation. 



For the last two sorts of birds mentioned, as the 

 stomach changes, the diet changes; beetles become a 

 part of the daily fare, until by the time the blackbirds 

 are half -grown their stomachs are ready to digest such 

 hard grains as corn. This may be given to them freely, 

 and when they leave the nest, corn may form one-fourth 

 of their diet. 



Following is a tabulated list of our most common 

 birds with the nestling, and, in some cases, adult food 

 habits. 



Brown Thrashers. Adults eat one-fourth fruit and 

 three-fourths insects; but the nestlings are exclusively 

 insectivorous. 



Mocking Bird. Adult eats fruit and insects, half and 

 half ; but feeds its nestlings exclusively on insects, such as 

 caterpillars, spiders, flies, moths, and butterflies. 



Catbird nestlings are fed on fruit to four per cent, 

 of their diet, the other ninety-six per cent being insects, 

 such as spiders, ants, caterpillars, and grasshoppers. 



Cuckoos, black-billed and yellow-billed, prefer a 

 caterpillar diet to any other kind, and this is varied with 

 leaf -eating larvse. One stomach examined contained two- 

 hundred fifty caterpillars. The hairs of a caterpillar are 

 usually barbed at the end, and are apt to catch in the 

 soft mucous lining of the cuckoo's stomach; hence the 

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