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TYRANNIDiE, FLYCATCHERS. 



Subfamihj TTRANNINJE, True Tyrants, 



presenting tbo following characters : — Wings oi 10 primaries, the 1st never spurious 

 nor very short, one or more frequently emarginate or attenuate on the inner web 



near the end. Tail of 12 rectrices, usually nearly even, 

 sometimes deepljr forflcate. Feet small, weak, exclu- 

 sively fitted for perching ; the tarsus little if any longer 

 than the middle toe and claw, the anterior toes, 

 especially the outer, extensivelj' coherent at base. 

 Bill very broad and more or less depressed at the base, 

 and tapering to a fine point, thus presenting a more or 

 less perfectly triangular outline when viewed from 

 above ; the tip abruptly deflected and usually plainly 

 notched just behind the bend ; the culmen smooth and 

 rounded transversely, straight or nearly so lengthwise, 

 except towards the end ; the commissure straight (or 

 slightly curved) except at the end ; the gonys long, flat, 

 not keeled. Nostrils small, circular, strictly basal, 

 overhung but not concealed by bristles. Mouth capa- 

 cious, its roof somewhat excavated, the rictus ample 

 and deeplj' cleft, the commissural point almost beneath 

 the anterior border of the eye. Rictus beset with a 

 number of long stiff bristles, sometimes reaching nearly 

 to the end of the bill, but generally shorter, and flaring 

 outward on each side ; there are other bristles or 

 bristle-tipped feathers about the base of the bill. The 

 bill is very light, gives a resonant sound, in dried 

 specimens, when tapped, and on being broken open, 

 the upper mandible will be found extensively hollow. 

 These several peculiarities of the bill are the more obvious and important features 

 of the group ; and will prevent our small olivaceous flycatchers from being con- 

 founded with insectivorous Oscines, as the warblers and vireos. 



The structure of the bill is admirably adapted for the capture of winged insects ; 

 the broad and deepl}^ fissured mandiljles form a capacious mouth, while the long 

 bristles are of service in entangling the creatures in the trap and restraining their 

 struggles to escape. The shape of the wings and tail confers the power of rapid 

 and varied aerial evolutions necessary for the successful pursuit of active flying 

 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 some prominent 

 outpost, in a peculiar attitude, with the wings and tail drooped and vibrating in 

 readiness for instant action ; and of dashing into the air, seizing the passing insect 

 with a quick movement and a click of the bill, and then returning to their stand. 

 Although some Oscines have somewhat the same habits, these pursue insects from 

 place to place, instead of perching in wait at a particular spot, and their forays are 

 not made with such admirable Han. Dependent entirely upon insect food, the 

 species arc necessarily migratory in our latitudes ; they appear with great regularity 

 in spring, and depart on the first approach of cold weather in the fall. They are 

 distributed over temperate North America ; many of them are common birds of the 

 Eastern States. The voice, susceptible of little modulation, is usually harsh and 



Fig. 110. Emargination of primaries 

 in Tyrannidce. 



