160 BULLETIN 17 9, UNITED STATES NATIONAL MUSEUM 



and one-year-old young birds have a complete molt in July and 

 August.] 



Food. — The most comprehensive accounts of the food habits of the 

 black phoebe are those of Prof. F. E. L. Beal (1910 and 1912), who 

 asserts that "this bird eats a higher percentage of insects than any 

 flycatcher yet studied except the western wood pewee." For the 

 earlier report there were available 333 stomachs, which showed 99.39 

 percent of animal matter to 0.61 percent of vegetable. Ground beetles 

 (Carabidae), ladybirds (Coccinellidae), and tiger beetles (Cicin- 

 delidae), all presumed to be useful, made up 2.82 percent. Other 

 beetles, all more or less harmful, amounted to 10 percent, consumed 

 throughout the year. Hymenoptera, principally wild bees and wasps, 

 contributed 35 percent, rising to 60 percent in the month of August. 

 No trace of a honeybee was found. 



Hemiptera, including plant lice and a number of aquatic species, 

 formed 7 percent of the total. Flies (Diptera) ranged from 3 per- 

 cent in August to 64 percent in April, averaging 28 percent. Grass- 

 hoppers and crickets supplied only about 2.5 percent, moths and 

 caterpillars 8 percent, miscellaneous, principally dragonflies, with 

 some spiders, 6 percent. In his second report, which differs little 

 from the first in percentages, Professor Beal adds that ants "for a 

 short time in midsummer constitute quite a notable part of the food." 



In the stomachs of 24 nestlings, tabulated separately from the 

 adults, "no great difference was apparent in the kind of food eaten 

 nor in the relative proportions," except that the percentage of vege- 

 table matter was a trifle higher. Regarding the consumption of 

 vegetable matter. Professor Beal (1912) says: "It is not at all improb- 

 able that this species and many others seldom or never take vege- 

 table food intentionally. In many cases the vegetable substance 

 found in the stomachs is mere rubbish accidentally picked up with 

 insects. Bees and wasps often light on berries to suck the juice, 

 and a bird making a quick snap at such an insect might take berry 

 and all." However, Prof. A. J. Cook (1896) found pepperberries 

 in the stomachs of nearly all black phoebes killed in whiter 

 (presumably in southern California). 



In towns and cities much of the bird's hunting is done by skim- 

 ming low over lawns, where it seems to capture a goodly number of 

 fair-sized moths, probably adults of the highly injurious cutworm. 



Mr. Oberlander (1939) found that indigestible portions of large 

 insects were regurgitated in the form of spherical or conical pellets 

 usually 7 or 8 millimeters in diameter. A pellet was ejected nearly 

 every night except in rainy weather, and with undetermined fre- 

 quency during the day. He also mentions an item of diet which is 



