162 BIRDS IX THEIR RELATIONS TO MAX. 



Their greatest depredations are committed in the grain-fields 

 of the Mississippi Valley and in the southern rice-fields. 



In an examination of seven hundred and twenty-five 

 stomachs the Department of Agriculture found seventy-four 

 per cent, of the food to be vegetable matter, the remainder 

 being animal, mainly insects. Weevils and snout-beetles 

 amounted to twenty-five per cent, of the June food. Beetles 

 formed ten per cent, of the food for the year ; grasshoppers 

 formed about five per cent. Of grain only corn, wheat, and 

 oats were found : together they constituted thirteen per cent, 

 of the whole food. Weed seed, mainly ragweed, barn-grass, 

 and smartweed, amounted to fifty-seven per cent. A sum- 

 mary of the food examined reveals the fact that about seven- 

 eighths of the red-wing's diet is made up of noxious insects 

 and weed seed. Therefore, while locally guilty of damage 

 sufficient to justify its slaughter, it would be very poor 

 economy to persecute this bird generally. 



The food of the young birds consists almost wholly of in- 

 sects of the sorts commonly eaten by the adults. 



The Cow-BiRD is found throughout the United States, except 

 along the Pacific coast. Its name was given in recognition of 

 its fondness for bovine society. It is essentially a bird of the 

 field, spending nearly all its time searching for food in fields 

 and pastures. It eats insects, grasshoppers, beetles, larvae, 

 etc., in summer, and takes seeds of weeds and occasionally 

 small grains at other seasons to a considerable extent. So 

 far as its food habits are concerned, there is much to commend 

 it, but as a parasite on other birds it is undoubtedly noxious. 



Its domestic relations are decidedly irregular. Males are 

 more numerous than females. Polyandry is a common prac- 

 tice. They never pair. They never build nests. By stealth 

 eggs are deposited in other birds' nests, to be hatched and the 

 young raised by foster-parents. Here is where the cow-birds 

 are criminal in effect if not in intention. The cow-bird egg 

 is laid with an uncompleted clutch. It hatches more quickly 



