240 USEFUL BIRDS. 



primary parasites, then numbers of Kingbirds were attracted 

 by the flying moths. It seems quite probable, therefore, that 

 the destruction of parasitic insects by Kingbirds is as likely 

 to be beneficial in such cases as injurious. 1 As about ninety 

 per cent, of the Kingbird's food consists of insects mostly 

 injurious ; as it has never yet been shown to be positively 

 harmful in any respect ; and as it acts as a protector to small 

 birds and poultry on the farm, — there need be nothing further 

 said to commend the bird to the farmer. 



HUMMINGBIRDS. 



The Hummingbirds are popularly believed to feed solely 

 upon the nectar of flowers ; but they are probably of con- 

 siderable economic importance, for the reason that, because 

 of their small size and long, slender beaks, they capture 

 many tiny insects that conceal themselves among the blos- 

 soms and foliage. Only one species of this distinctively 

 American family has been found in Massachusetts. 



Ruby-throated Hummingbird. 



Trochilus colubris. 



Length. — About three and three-fourths inches. 



Adult Male. — Above, bright, glossy green ; throat metallic ruby-red ; lower parts 



white. 

 Female and Young. — Similar, hut without red on throat. 

 Nest. — A shallow little cup of soft, downy materials, covered externally with 



lichens, looking like a "moss-covered" knot on a branch; from five to 



sixty feet up. 

 Eggs. — White. 

 Season. — May to September. 



This dainty, feathered gem, the smallest of all native birds, 

 comes to us from the tropics when the south wind blows in 

 May, and when bursting buds and flowers first afford it the 

 honey, nectar, and tiny insects on which it lives. Often 

 when the cherry trees are in bloom many of these little sprites 



1 It would seem from the above that the Kingbird was doubly useful : first, in 

 killing the gipsy moth ; second, in protecting the parasites of the gipsy moth from 

 secondary parasites. But there may be some doubt regarding the habits of this 

 Theronia. It is named by Professor Fernald (Monograph of the Gipsy Moth, 

 Forbush-Fernald, 1896, p. 376) as one of the most useful primary parasites of the 

 gipsy moth, although he states that Mr. C. E. Bailey captured a specimen in the 

 act of stinging a gipsy pupa that was already parasitized by a dipterous insect. 



