240 USEFUL BIRDS. 
primary parasites, then numbers of Kingbirds were attracted 
by the flying moths. Itseems 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, but 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 
+ 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. 
