BIRDS OF PENNSYLVANIA. 



145 



In addition to Audubon's observations on the food habits and my 

 own examinations given in the above table, it might be added that in 

 March and April, 1885, I shot seventeen of these birds in the Florida 

 orange orchards and found that all had only insects in their viscera. 

 May 14, 1886, I received from Mr. George Hartman, of West Chester, 

 Pa., fifteen Hummers which had been captured while feeding among 

 the flowers of a horse-chestnut tree. The stomachs of these birds, 

 which were kindly examined fqr me by Prof. C. V. Riley, entomolo- 

 gist. United States Department of Agriculture, Washington, D. C., 

 showed chiefly the remains of small spiders and some few coleopte- 

 rous insects. 



ORDER PASSEBES. PERCHING BIRDS. 



SUBORDER CLAMATORES. SOXGLESS PERCHING BIRDS. 

 FAMILY TYRANNID-ffl. TYRANT FLYCATCHERS, f 



* These seventeen birds were all killed when feeding in horse-chestnut trees. 



tOf the several species of this highly beneficial family which occur in Pennsylvania as sum- 

 mer residents or passing visitants but two, viz : the King-bird and and common Pewee, are gen- 

 erally known to those who are not interested in ornithological pursuits. Both of these birds are 

 common breeders about the habitations of man, and unlike most others of their kin are not shy 

 or difficult to approach. Although at times some of the Flycatchers descend to the earth for 

 food, it is safe to say that these birds, collectively considered, are seldom observed on the 

 ground leeding. "The structure of the bill is admirably adapted for the capture of winged 

 insects : the broad and deeply fissured mandibles form a capacious mouth, while the long bristles 

 are of service in entangling the creatures in a trap and restraining their struggles to escape. 

 The shape of the wings and tail confers the power of rapid and varied aerial evolutions necessary 

 1'or the successful pursuit of active Hying insects. A little practice in field ornithology will 

 enable one to recognize the flycatchers from their habit of perching in wait for their prey upon 



10 BIRDS. 



