BLACK PHOEBE. 39 



examination of stomachs confirms field observations. But few fly- 

 catchers, or birds of any kind, devour a larger percentage of insect 

 food than the black phoebe. It is not at all improvable that this 

 species and many others seldom or never take vegetable food inten- 

 tionally. In many cases the vegetable substance found in the stom- 

 achs 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, and when the 

 seeds were found in its stomach it might be charged with having 

 intentionally eaten the fruit. 



For the laboratory investigation of this bird's food 344 stomachs 

 were available, all but one collected in California, but distributed 

 through every month of the year. The food was found to consist of 

 99.41 per cent of animal matter to 0.59 per cent of vegetable. 



Animal food. — Useful beetles belonging to the three families Cicin- 

 delidse, Carabidse, and Coccineflidse were found in 15 stomachs and 

 amount to 2.82 per cent of the food. Other beetles of harmful or 

 neutral species were found in 41 stomachs and reach 10.50 per cent. 

 Hymenoptera form the largest item of the food. They were found 

 in 247 stomachs and were the whole contents of 15. There is a good 

 percentage in every month except March and April, and these excep- 

 tions are probably accidental. As would naturally be expected, the 

 greatest amount is eaten in August, when it aggregates 58.75 per cent 

 of the food. The average for the year is 30.82 per cent. A few 

 parasitic species were noted, but they were too few to make a respect- 

 able percentage. Ants were found in 48 stomachs, and for a short 

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

 Various wild bees and wasps make up the bulk of this item. No 

 honeybees were found. 



Hemiptera, or bugs in various forms, constitute 10.56 per cent and 

 were found in the stomachs of every month but May. December is 

 the month of greatest consumption and April and May of least. 

 They were found in 92 stomachs, and 13 families were identified. 

 Pentatomidae, or stinkbugs, appear to be the favorites, as they were 

 contained in 10 stomachs, the most of any family. Plant lice 

 (Aphidse) were found in 1 stomach. Diptera, or flies, amount to 

 28.26 per cent and form the second largest item. They were found 

 in 97 stomachs and completely filled 3. They constitute the most 

 regular article in the black phcebe's diet. Every month has a good 

 percentage, except perhaps August, which shows only 4.92, but the 

 next one is July, with 11.47, and all the others are higher. The 

 maximum occurs in April at 64.36 per cent. The black phoebe fairly 

 merits its title of flycatcher. 



Lepidoptera (moths and caterpillars) amount to 8.22 per cent of 

 the food. They were found in 72 stomachs, of which 51 contained 



