FOOD HABITS OF THE VIREOS 15 
to figure in the food only incidentally, but after the height of the 
insect season has passed the birds turn to the ripe fruits as a source 
of supply. Thus in April the vegetable matter formed but 0.12 
per cent, but in August and September it ran as high as 18.69 and 
9.33 per cent, respectively. Of the total food, this item makes up 
5.76 per cent. 
SUMMARY 
The economic status of the warbling vireo is in some ways more 
distinctly unfavorable than that of the other species of this family 
of birds, especially in its consumption of ladybirds. In more than 
a third of the stomachs examined the remains of these beneficial 
beetles were found. Destruction of ladybirds is most evident in 
stomachs collected in California, where the members of this group 
of beetles are known to be unusually common. The species known 
as the California ladybird leads the list in number, appearing in 41 
stomachs, as high as eight to a single stomach in a few instances. 
A second category of insects, which from predacious habits are to be 
considered beneficial to man, is made up of the species of stink-bugs 
of the genus Podisus, detected in 18 stomachs. Owing to their size, 
a few will completely fill the stomach of the bird, and thus the 
likelihood of extensive meals so far as numbers of the insects are 
concerned is not great. 
On the other hand, the injurious insects taken by the warbling 
vireo make up the greater part of the food. Lepidopterous remains, 
including adult moths and butterflies, caterpillars, pupae, and eggs, 
were taken from about 77 per cent of those examined. This alone 
should atone for the bird's injurious proclivities along other lines. 
In addition to lepidopterans, the consumption of scale insects, which 
were found in 18 stomachs, and of bugs, omitting the forms of Podisus 
and a few others, swells the total of injurious kinds consumed. 
Little if any of the vegetable food taken was obviously cultivated, 
in most cases being from plants not used for their fruits. It seems 
reasonable, then, to class the bird as neither beneficial nor injurious. 
It is probable that a ws,rbling vireo in a citrus grove would be 
economically a liability, but in the woods and other places where the 
conservation of coccinellids is not of so great importance there is little 
to be considered objectionable in its habits. 
YELLOW-THROATED VIREO 
Lanivireo flavifrons 
The yellow- throated vireo is the handsomest of the family and 
spends much of its time high up in the trees. This species is not 
uncommon in the eastern part of the United States, where it remains 
during the summer months to breed. It arrives in Florida and 
Texas about the last of March and by the first week in May many 
individuals have reached their breeding grounds. The return 
migration in fall commences early in September, and by October 
there are few birds of this species left in the United States. 
One hundred and sixty stomachs of the yellow-throated vireo, 
collected during the months April to September, inclusive, were 
available for analysis, the most noticeable fact established by the 
