FOOD HABITS OF THE VIREOS 
ANIMAL FOOD 
Practically six-sevenths of the food consumed by the red-eye is 
of animal origin, and very nearly all of it is insects. The remainder 
is composed of the ,small snails that are found more or less fre- 
quently on leaves and grass. 
Lepidoptera. — -Caterpillars form by far the largest single item in 
the yearly sustenance, and amount to 32.43 per cent of the total, or 
more than one- third of the animal matter eaten. They were found 
in 371 of the stomachs, over half of the number examined. In 
general it is difficult or even impossible to identify the species of 
caterpillars found in stomachs, but the larvae of sphinx moths, 
swallowtail butterflies, tent caterpillars, and codling moths were 
detected. Most caterpillars are injurious to man's interests or have 
characteristics which at any time may cause them to become so. 
Hence, so great a destruction of these larvae as the figures show is a 
strong argument in favor of this vireo. 
Lepidopterous forms other than caterpillars make up a small 
percentage (2.76) of the annual food. Adult moths and butterflies 
were found in 26 stomachs, pupae (cocoons and chrysalids) in 14, 
and eggs in 3. These may all be placed with caterpillars as injurious 
forms. 
Coleoptera. — Beetles make up 10.84 per cent of the total food for 
the year, 1.29 per cent of which is composed of lady beetles. Lady 
beetles, or " ladybirds," as the members of the family Coccinellidae 
are often called, are, with a very few exceptions, decidedly beneficial 
to man's interests. Eighty-five of the stomachs examined contained 
coccinellids, some from three to eight individuals each. It can only 
be said that, considered in connection with all the food taken, the 
destruction of lady beetles is more than repaid by beneficial activities 
in other directions. 
Scarabaeid beetles, otherwise known as "leaf chafers" and "dung 
beetles," form a small item in the yearly food of this bird. During 
June, when the larger leaf-infesting species are in greatest abundance, 
the percentage of this item rose to 11.88. Among the forms recog- 
nized are many species of the medium-sized and robust brown leaf 
chafers, which are capable of considerable damage. Scarabaeids 
were found in 75 of the 569 stomachs examined and made a total of 
3.31 per cent of the food. 
Leaf beetles ( Chrysomelidae) are injurious in their feeding habits; 
hence the quantity taken by the vireo is to be considered a gain to 
man. Though a species of leaf beetle may be known to attack 
only wild plants, there is always the possibility that it may adapt 
itself at any time to life among the cultivated plants, shrubs, or trees, 
and with that adaptation become detrimental to man's interests. 
Examination of the stomachs shows that the percentage of leaf 
beetles rises to 4.4 in May, after which it becomes less, disappearing 
entirely in October. In fact, the percentages vary directly with the 
abundance of the item, as is to be expected. Considered as part of 
the annual diet, chrysomelids make up 1.63 per cent and were found 
in 136 of the stomachs examined. 
Representatives of the three families Cerambycidae, Buprestidae, 
and Elateridae have been grouped for convenience. The larvae, or 
grubs, of all these beetles pass their lives either within wood or among 
the roots of plants and are very destructive to lumber and grain 
