FAMILY HIRUNDINID^E 



and their graceful flight, cheerful conver- 

 sational notes (though few of them have 

 much of a song) , and insect destroying habits 

 make them welcome about human habita- 

 tions, many of them nesting about buildings 

 or in bird houses placed for them. 



Swallows are not likely to be mistaken for, 

 or confused with, any other birds except the 

 swifts. The latter, however, have narrower, 

 usually more or less curved, wings and a 

 characteristic manner of flight that the bird 

 student will soon learn to distinguish. 



Key to the Swallows 



A. Tail noticeably elongate and deeply forked. Back 



steel blue, throat and chest rufous 



Hirundo crythrogaster 



AA. Tail not elongated; notched, or slightly, but not 

 deeply, forked. 



a. Upper parts (including rump) of uniform or nearly 

 uniform color. 



b. Back sooty black, blue black or steel blue. 



c. Very small, length 102 mm. (4.00 in.). Gen- 

 eral color sooty black, slightly lighter below 

 Neochelidon tibialis 



cc. Size large, length 165 mm. (6.50 in.), back steel 

 blue or blue black (more sooty) in young; 

 under parts grayish brown shading to white 

 on abdomen Progne c. chalybea 



bb. Upper parts grayish brown. Lower parts 

 white with a broad grayish brown band across 

 chest Riparia riparia 



aa. Rump noticeably different in color from rest of 

 upper parts. 



b. Rump white or whitish. 



c. Rump conspicuously white. Rest of back 

 steel blue in adults, drab gray in young. 

 Lower parts white Iridoprocne albilinea 



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