FAMILY TROCHILIDjE 



are usually more plainly colored and those of 

 most species are so much alike that their 

 recognition in life is difficult or impossible. 



Key to the Male Hummingbirds 



a. Extremely small, length about 67 mm. (2.60 in.); a 

 conspicuous crest of elongated tawny feathers; a 

 buffy line across rump Lophornis delattrei 



aa. Larger, length 77 mm. (3.00 in.) or more; no crest. 



b. Underparts mainly dull buffy, grayish tawny or 

 grayish rufous without bright metallic coloring; 

 bill relatively very long and curved; size medium 

 to small. 



c. Tail broad and rounded ; under parts dull rufous . . 

 Glaucis hirsuta affinis 



cc. Tail not broad and rounded. 



d. Middle tail feathers excessively elongated, 

 terminally white. 



e. Upper parts bright metallic bluish green; 



rump metallic greenish blue 



Phosthornis guyi coruscus 



ee. Upper parts dull metallic bronze, tbe rump 



tawny barred with black 



Phcethornis longirostris cassini 



dd. Middle tail feathers not excessively elongated 

 but tail extremely graduated. 



e. Larger, length about no mm. (4.30 in.); 

 rump metallic bronzy green ; a tawny chest- 

 nut area on throat and chest 



Threnetes ruckeri dariensis 



ee. Smaller, length about 87 mm. (3.40 in.); 

 rump chestnut; under parts dull grayish 

 tawny Plwethornis adolphi nelsoni 



bb. Under parts not mainly dull buffy, grayish tawny 

 or grayish rufous. With or without metallic 

 coloring below. 



c. Under parts with extensive and conspicuous white 

 areas. 



d. Tail extensively white. 

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