ECONOMIC RELATIONS OF OUR BIRDS. 
479 
Tabular Summary of Economic Relations showing the number of specimens con¬ 
taining animal and vegetable food, and the number of insects and spiders 
taken from the stomachs, classified as to economic relations under the heads 
Beneficial, Detrimental and Unknown Relations. 
Number and Name of Speci¬ 
mens Examined. 
Classification 
OF Food. 
Ratios Represented by Lines. 
26 
Animal food. 
1 
O 
Vegetal food. 
B 
Of twenty-seven Bluebirds 
20 
.9 
42 
examined. 
8 
-2 
a 
o 
o 
5 
Beneficial. 
11 
22 
Unknown. 
Table showing the kinds and number of insects and spiders eaten by the 
Bluebird. 
Number and Name of Speci¬ 
mens Examined. 
Of twenty-seven Bluebirds 
examined. 
1 
6 
8 
1 
17 
2 
24 
6 
2 
■a 
aj 
rt 
a 
o 
o 
Classification 
OF Food. 
Ratios Represented by Lines. 
2 
Ants. 
1 
10 
Lepidoptera. 
13 
Beetles. 
1 
Heteroptera. 
1 
22 
Orthoptera. 
2 
Spiders. 
D 
40 
Adult forms. 
■iMii>iwj!ra.<'^...!wi«’'JWBiiii yi—Iiiimuun 
9 
Larvee.. 
10 
Grasshopper eggs. 
^BBESS^DS 
10. SiALiA siALis (Linn.), Hald. EASTERN BLUEBIRD. Group I. Class b. 
The Bluebird has so many excellent qualities that it promises to become, 
under proper management, one of the most readily utilizable insect-destroyers 
which we have among birds. It is, with us, almost exclusively insectivorous, 
and is especially destructive to grasshoppers. It captures its prey upon the wing 
and upon the ground, giving it a wide range of food, from which it may be ex¬ 
pected to maintain, under favorable conditions, a steady and considerable abun¬ 
dance. Its long summer residence, its rearing of two, sometimes three, broods 
each season, its fondness for cultivated fields, and its willingness to breed in 
bird-houses pi’otected from the ordinary enemies of birds, and beyond the dis¬ 
turbance of the machinery and live-stock of the farm, are other qualifications 
which tend to place it in the front rank of usefulness. 
How to cause this bird to take and maintain a greater abundance than it now 
has is a question of great practical importance to all classes of farming. The 
fact that its familiar and confiding nature has not made it more numerous among 
us, appears to be readily explained by its breeding habits. In its unmodified 
condition, its nest is usually placed in some hollow limb or tree; and as a natural 
