106 The Food of Birds. 



three-fourths of the food of eleven specimens, and in 

 March more than a third of the food of nine. Wliile this lar- 

 va is not at present injurious, but feeds ordinarily on decay- 

 ing vegetation, it might possibly do injury to meadows 

 and pastures if allowed to multiply without restraint. 



But few ants are eaten by this bird until late in the fall, 

 when the swarming of the sexual forms of some of the 

 species seems to attract its appetite, in the relative dearth 

 of other insects. 



Caterpillars make up, in March, April and May, fully 

 a fourth of its food, about half of these being cutworms 

 and other similar forms. Later, these are largely given 

 up for fruit, and in the latter half of the season make only 

 about one-tenth of the food. The average of caterpillars 

 for the year is seventeen per cent. 



Beetles, commencing at four per cent, in February, when 

 but few specimens have yet been aroused from their cold 

 winter's sleep, rise to forty-four per cent, in April and 

 May, when their procreative energies are most active and 

 urge them out into the air in swarms. With the appear- 

 ance of the small fruits, beetles, also, are neglected by the 

 robin, and the average for the last four months of the sea- 

 son falls away to six per cent., eighteen being that for the 

 year. 



This discrimination affects chiefly the scavenger beetles 

 and the "June beetles," the other families maintaining 

 about their original numbers throughout, with only an up- 

 ward wave in April. The predaceous beetles average six 

 per cent, of the food of the year, the leaf-chafers three 

 per cent., the wire worms two per cent., and the snout- 

 beetles one per cent. 



The robin's depredations upon the true bugs ( Hemiptera) 

 are but trivial, amounting only to three per cent, of the 

 food, but nearly all of these belong to species regarded 

 more or less positively as beneficial. 



The ratio of grasshoppers and crickets (four per cent.) 

 seems trivial at first sight. We note, however, that these 

 were eaten by twenty-six of the birds, and that, conse- 

 quently, at least twenty-six of the insects must have been 

 destroyed. Remembering that these figures are based 



