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202 THE CONDOR VoL XIII frightened they perched in some nearby fir trees or on the telegraph. wires. The third flock could always be found in the near vicinity of some meadow-land south of Sisson. Close observation failed to show them feeding on anything but butterflies. The stomach examination of the few Brewers taken at this time substantiated the fact that their food was made up almost entirely of the butterflies. The stomach of one bird taken very early in .the morning, when examined, was found to contain five Eu?onia californica and parts of several others. A few grains of oats and parts of beetles were found in the stomach of a bird taken in a meadow near a stubble field. Birds collected the latter part of June and July contained a large percentage of beetles but no larvae or adults of F.u?onia californica. Considering the comparative numbers of individuals of the different species of birds found to feed on the butterfly, the Brewer blackbird took 95 percent of the butterflies eaten by birds, the meadowlark 2 percent and the kingbird, blue jay and Say phoebe shared the rest. Only four western kingbirds (Tyrannus verticalis) were seen. Two birds perched on the telegraph wires along a road, were watched for some time. One of them was seen to catch two butterflies in the air. On another occasion two kingbirds were seen in the same general location, probably the same birds. They continu- ally flew out from the wire and caught some insect in the air. As the air was filled with butterflies, it seems probable that these birds were catching them. Two kingbirds seen perched on a fence in a barnyard appeared also to be feeding on butterflies. it is to be regretted that no specimens are at hand for stomach exam- ination,.as the supplementary evidence, ?thus obtainable, would have thrown light on the extent to which the kingbird acts as a check. Meadowlarks (Slumella neg, lecta) were so shy that except in one case, it was impossible to determine the kind of food taken. A lone meadowlark feeding with some Brewer blackbirds on the grass plot adjoining the station was seen to run after several butterflies and to catch one. In the examination of seven stomachs, only two showed the remains of butterflies..All of the birds whose stomachs were examined, were taken in meadows or cut fields of wild hay where other insect life was abundant. Beetles and grasshoppers formed the bulk of the food. A Say phoebe (Sayornis sayus) collected August 30, was found to contain a large butterfly of another species and also a Eug, onia californica, as well as some ants. Since 75 percent of the stomach contents was composed of butterflies of dif- ferent kinds and since, according to Beal (1910), these insects form more than 10 percent of the food of this bird for the year, it would appear that this flycatcher, as well as the kingbird, can be ranked as one of the checks on Eug, onia californica. Doubtless another large flycatcher, the ash-throated flycatcher (Myiarchus ciner- ascens), took its share of the butterflies, for it is known to feed to a considerable extent on butterflies and moths. No specimens of this species are available. If the food of the smaller flycatchers can be judged from that of the western fiycatcher(Empidonax difficilis) it is doubtful if they bore any relation to the out- break. The stomachs of the two western flycatchers examined, contained numer- Ous small flies and a few small bees and beetles. A small white moth was found in one of the stomachs. Moreover it seems strange that a bird of its size should take so large an insect as the butterfly under discussion. No specimens of the western wood pewee (WfYiochanes ?ichardsoni) are at hand. Its food habits are known to be much like those of the western flycatcher. The red-winged blackbird (Agelaius phoeniceus, subspecies ?) was very abund-