48 



BIRDS OF A MAEYLAND FAEM. 



to illustrate this habit was not available at Marshall Hall, but the 

 diagrams here given (figs. IT and 18), based on results obtained 

 elsewhere/' will serve to show it. By the time the young are ready 

 to leave the nest, however, they are fed to a large extent on either 

 grain or fruit, according to locality. In the Middle West they take 

 grain and in the East generally fruit. Both crows and crow black- 



7 DAYS OR LESS 



1 TO 2 WEEKS OLD 



3WEEKS AND OLDER ADULT 



Fig. 17. — Diagram showing proportions of food of American crow ( C'orvusamericanus),yonng and adult. 



birds do great service by feeding to their young not only cutworms 

 and grasshoppers, but also large numbers of weevils and May-beetles. 



GENERAL REMARKS. 



Consumption of caterpillars and grasshoppers is the largest benefit 

 derived from the presence of nestlings on the farm. The parent birds 



^ Most of the stomachs of young and adult crows used in the investigation on 

 which the results shown in the diagram are based were obtained at Sandy Spring, 

 Md. ; and most of those of young and adult crow blackbirds came from Onaga, Kans. 



