28 BIRDS OF CALIFORNIA AFFECTING FRUIT INDUSTRY. 
as insect destroyers. They do not consume any product of hus- 
bandry, and the worst that can be said of them is that they eat some 
useful insects with the harmful ones, though the former are in a 
very decided minority. This statement, however, applies to any and 
all insect-eating birds. It would be just as reasonable to expect.a 
mower or reaper to cut grain and leave the weeds standing as to sup- 
pose that from the hordes of insects around us birds will select only 
the ones that are injurious to man and leave untouched those that.are 
beneficial. Then, too, a superabundance of any species of insects, 
even beneficial ones, would be a nuisance. The service which strad- 
lows render is to prey upon the whole insect tribe and so to reduce 
the flood of insect life to a lower level where it may be more easily 
dealt with by man. 
CLIFF SWALLOW. 
(Petrochelidon lunifrons.) 
In the Eastern States the cliff swallow has practically abandoned 
its original nesting sites under cliffs, and now nests under the eaves 
of houses and other buildings. The writer has counted 80 nests 
beneath the eaves of 1 barn. In California the bird has taken up 
with the new order of things to some extent, but has not entirely 
abandoned its old habits. It is a migrant and remains in the State 
for about six months only during the breeding season, which is the 
time when the bird does the most good. 
The following discussion of the food of the cliff swallow is based 
upon the examination of 123 stomachs, representing every month 
from April to September, inclusive. 
Vegetable food —Vegetable food to the extent of 0.32 of 1 percent! 
was found. In most cases this was simply rubbish taken acciden- 
tally, though it includes a few small seeds. 
.lnimal food —Of the animal matter the largest item is Hymenop- 
tera. These insects formed over 39 percent of the total food; most 
of them were bees and wasps, and small parasitic species were identi- 
fied in a number of stomachs; a few were ants. Unfortunately, 
Inany parasitic insects are eaten by birds that take their prey upon 
the wing, such as swallows and flycatchers. The fact is to be 
deplored, but in most cases the percentage ix not large.» Perhaps the 
most interesting insect among Hymenoptera eaten is the common 
honey-hee (Cl pix mellifera). Of these, 34 were identified, all con- 
tained in LL stomachs, in one of which were 8 individuals. AIL were 
drones—that is, males. Nota trace of a worker bee was found. In 
two stomachs drones constituted the whole food and in several others 
the principal part. Tt is probable that most of them were taken 
when the queen made her marriage flight. So far as the writer has 
