OLIVE-SIDED FLYCATCHER. 41 



Food of nestlings. — Among the stomachs involved in the foregoing 

 discussion are those of 22 nestlings varying in age from 1 to 2 weeks. 

 These were separately tabulated, and show some differences from the 

 diet of the adults. The food consisted of 98.86 per cent of animal 

 matter to 1.14 of vegetable. This is apparently more than twice as 

 much vegetable matter as was taken by the adults, but nearly all of 

 t was rubbish, probably given to the young accidentally. Only 1 

 stomach contained a little fruit pulp — real food. Beetles, which are 

 hard food, amount to 3.14 per cent. Hymenoptera, which are softer 

 and much more easily crushed and broken up, aggregate 44.68 per 

 cent. Hemiptera (bugs) were fed to 1 nestling only. It was 17 per 

 cent of that stomach's contents, but amounts to only 0.77 per cent 

 of the whole food. Diptera, which are softer than Hymenoptera, 

 were fed to the amount of 34.73 per cent. In 1 brood of 3 the average 

 in each stomach was 75 per cent, and in another brood of 3 the aver- 

 age was 82 per cent. In 2 other broods none at all were found. 

 Lepidoptera reached a percentage of 8.23 per cent, but were irregu- 

 larly distributed; that is, they were fed to only 6 of the 22 birds, but 

 to an average extent of over 30 per cent to each. Crickets were fed 

 to but 1 of the nestlings, but in that 1 they amounted to 85 per ceDt, 

 making an average of 3.86 per cent for all. Dragon flies were fed to 

 3 birds of different broods to the extent of 10, 15, and 30 per cent, 

 respectively. The average for the 22 is 2.50 per cent. It will be 

 noted that the nestlings' food is on the whole composed of much 

 softer constituents than that eaten by the adults. If we take the 

 three softest elements — Hymenoptera, Diptera, and Lepidoptera — we 

 find that they aggregate 87.64 per cent of the whole food. 



Summary. — While the black phoebe does not improve every 

 opportunity to destroy harmful insects, it certainly neglects many 

 chances to eat useful ones. The destruction of a few predaceous 

 beetles, dragon flies, and parasitic Hymenoptera are the sum of its 

 sinning. So far as the writer knows, this bird is welcomed and pro- 

 tected everywhere throughout its range, which is as it should be. 



OLIVE-SIDED FLYCATCHER. 



( Nuttallornis borealis.) 



The olive-sided flycatcher appears to be an inhabitant of North 

 America at large, but is nowhere very abundant. It breeds in scat- 

 tered localities throughout the United States; in the southern part 

 only in the mountains. It shows a decided preference for mountain- 

 ous regions and coniferous forests; consequently it is not often seen 

 about orchards and gardens .and does not usually come in contact 

 with crops. Interest in its food, therefore, is to a certain degree 

 academic. Its food habits, however, are notable from the fact that 

 this species represents the extreme of the flycatcher type. Of the 



