e
need peruse only a few pages to become impressed with the fact that our
Government Biological Survey has made an {105} exhaustive and
exceedingly thorough investigation of the feeding habits of the wild
birds that frequent the fields and forests. The reports of the
economic ornithologists herein given are almost as surprising as the
sad records given by the entomologists in the Year Book. We learn that
birds, as a class, constitute a great natural check on the undue
increase of harmful insects, and furthermore that the capacity for food
of the average bird is decidedly greater in proportion than that of any
other vertebrate.

_Some Useful Birds._--Most people who have made the acquaintance of our
common birds know the friendly little Chickadee, which winter and
summer is a constant resident in groves of deciduous trees. It feeds,
among other things, on borers living in the bark of trees, on plant
lice which suck the sap, on caterpillars which consume the leaves, and
on codling worms which destroy fruit. One naturalist found that four
Chickadees had eaten one hundred and five female cankerworm moths.
With scalpel, tweezers, and microscope these moths were examined, {106}
and each was found to contain on an average one hundred and eighty-five
eggs. This gives a total of nearly twenty thousand cankerworm moth
eggs destroyed by four birds in a few minutes. The Chickadee is very
fond of the eggs of this moth and hunts them assiduously during the
four weeks of the summer when the moths are laying them.

The Nighthawk, which feeds mainly in the evening, and which is equally
at home in the pine barrens of Florida, the prairies of Dakota, or the
upper air of New York City, is a slaughterer of insects of many kinds.
A Government agent collected one, in the stomach of which were the
remains of thirty-four May beetles, the larvae of which are the white
grubs well known to farmers on account of their destruction of potatoes
and other vegetables. Several stomachs have been found to contain
fifty or more different kinds of insects, and the number of individuals
in some cases run into the thousands. Nighthawks also eat
grasshoppers, potato-beetles, cucumber-beetles, boll-weevils,
leaf-hoppers, and numerous gnats and {107} mosquitoes. Surely this
splendid representative of the Goatsucker family deserves the gratitude
of all American citizens.

Among the branches of certain of our fruit trees we sometimes see large
webs wh