380 PRACTICAL ZOOLOGY 



ment by the owners of the farms. Certain species, such as 

 flycatchers, swallows, and warblers, prey to some extent upon 

 useful parasitic insects, but, on the whole, the habits of the in- 

 sectivorous birds are productive of considerable good. Together 

 with the vireos, cuckoos, and woodpeckers (exclusive of the sap- 

 suckers), they are the most valuable conservators of foliage on 

 the farms. The quail, meadow lark, orchard oriole, mocking 

 bird, house wren, grasshopper sparrow, and chipping sparrow 

 feed on insects of the cultivated fields, particularly during the 

 breeding season, when the nestlings of practically all species eat 

 enormous numbers of caterpillars and grasshoppers. 



" The most evident service is the wholesale destruction of 

 weed seed. Even if birds were useful in no other way, their 

 preservation would still be desirable, since in destroying large 

 quantities of weed seed they array themselves on the side of the 

 Marshall Hall farmer against invaders that dispute with him, 

 inch by inch, the possession of his fields. The most active weed 

 destroyers are the quail, dove, cowbird, red-winged blackbird, 

 meadow lark, and a dozen species of native sparrows. The 

 utility of these species in destroying weed seed is probably at 

 least as great wherever the birds may be found as investigation 

 has shown it to be at Marshall Hall." 



Domesticated Birds. - - Birds have for many centuries been 

 under the control of man, and have produced for him hundreds of 

 millions of dollars' worth of food and feathers every year. The 

 common hen was probably derived from the red jungle fowl of 

 northeastern and central India. The varieties of chickens that 

 have been derived from this species are almost infinite. 



The domestic pigeons are descendants of the wild, blue-rock 

 pigeon which ranges from Europe through the Mediterranean 

 countries to central Asia and China. Breeders have produced 

 over a score of varieties from this ancestral species, such as 

 carriers, pouters, fantails, and tumblers. Young pigeons, 

 called squabs, constitute a valuable article of food. 



Of less importance are the geese, ducks, turkeys, peacocks, 



