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204 THI? CONDOR Vol. XlII time of year is largely wild fruit.. Over 99 percent of the food contained in the stomachs of six birds taken near the huckleberries, was made up of this fruit. Cliff swallows (Petrochelidon lunifrons) were usually seen circling high in the air although on two occasions a number were seen perched on telegraph wires. These birds were carefully watched, but they did not seem to be feeding on the numerous butterflies about them. They certainly could have been seen to take butterflies if these'.?had been chosen for food. A very few Western barn swallows (Zlirundo erythrogastra) were seen, but these too, seemed to be intent on catch- ing some smaller insect. No stomachs are at hand for examination. Mountain quail ( Oreortyx picta plumifera) were very abundant in the brush. A flock was closely watched, but the birds appeared to be searching among the leaves under the brush for their food. As the mountain quail is largely a vegeta- rian, it probably bore no relation to the butterflies. The stomachs of three mourning doves (-7enaidura macroura carolinensis) contained nothing but weed seeds. One stomach of each of the following birds was also examined: belted king- fisher (Ceryle alcyon), western evening grosbeak (Zlesperiphona vespertina montana), Cassin purple finch ( Ckrpodacus cassini), Sierra junco (Junco hyemalis thurberi), and western house wren (Tro?lodytes aedon parkmani). There was no evidence that these birds fed on the butterflies. Judging from its food habits, it seems probable that the wren would be one of the birds to feed on the pupae. The Calaveras warbler (Vermivora rubricapilla gutturalis), another common bird of the brush, probably ranks with the western house wren in this regard. Chickens and ducks seemed to appreciate the unlimited supply of butterflies, for they were seen catching them from early morning till late in the evening. In the vicinity of Sisson, at least, the domestic birds, on account of their capacity and numbers, by destroying butterflies performed a service nearly as great as all the wild species put together. The following table gives a summary of the contents of the stomachs of birds taken during August, and the number of stomachs of each species examined. Number Percent Percent of Percent NAME OF SPECIES of of Ani- Vegetable of Stomachs real Food Food Butterflies Mourning dove (Zenaidura macroura carolinensis) 3 100.0 Belted kingfisher (Ceryle alcyon) 1 100.0 White-headed woodpecker (Xenopicus albolarvatus) 2 11.5 88.5 Red-shafted flicker (Colapies caret collaris) I 19.0 81.0 Say phoebe (Sayornis sayus) I 100.0 25.0 Western flycatcher (]?mpidonaa: difficilis) 2 100.0 Blue-fronted jay (Cyanocitta siellerifrontalis) 2 74.0 26.0 30.0 Red-winged blackbird (dgelaius phoeniceus, subsp.? ) 13 6.7 93.3 Western megdowlark (Sturnella neglecta) 5 85.? 14.6 15.2 Bullock oriole (Icierus bullocki) 4 17.5 82.5 Brewer blackbird (]ruphagus cyanocephalus) 3 83.3 16.7 61.0' Western evening grosbeak (Hesperiphona vespertina montana) 1 74.0 26. 0 Cassin purple finch (Carpodacus cassin:? 1 100.0 Brewer sparrow (Spizella breweri) 3 47.7 52.3 Sierra junco (/unco hyemalis thurberi) 1 100.0 Mountain song sparrow (Melospiza melodia monlana) 1 100.0 Thick-billed fox " (Passerella iliaca megarhyncha) 2 4.0 96.0 Green-tailed towbee (Oreospiza chlorura) 2 71.0 29.0 Western house wren ( Troglodytes aedon parkmani) 1 100.0 Western robin (Planesticus migratorius propinquus) 10 13.7 87.3 Western bluebird (Sialia mexicana occidenlalis) 2 86.5 13.5 Total number of stomachs 61 Average percent of butterflies taken by four birds ............................... 32.8 Average percent of butterflies taken by all birds ................................ 6.2