156 VERTEBRATES: BIRDS. 



The Black-chinned Humming-Bird, T. Alexandri^ 

 Fig. 99. Bourc. & Muls., of California and 



southward, is three inches and three 

 tenths long, and the wing one inch 

 and seven tenths. 



The Red-backed Humming-Bird, 

 Selasphorns rufus, Sw., of Western 



Humming-Bird's nest, North America, is three and a half 

 T. coinbris, Linn. inches long, and the wing over one 



inch and a half. 



The Broad-tailed Humming-Bird, 5". platycercus, Gould, 

 of Mexico and Texas, is three and a half inches long, and 

 the wing a little less than two inches. 



The Anna Humming-Bird, Atthis anna, Reichenb., of 

 California, is three and six tenths inches long, and the 

 wing two inches. 



The Ruffed Humming-Bird, A. costce, Reichenb., of 

 Southern California, is three and two tenths inches long, 

 and the wing one inch and three fourths. 



CYPSELID^E, OR SWIFT FAMILY. This Family com- 

 prises small, dull-colored birds, which have the general 

 appearance of swallows, but differ from the latter in 

 many essential characteristics. The Swifts have a much 

 smaller and shorter bill, with the edges greatly inflected ; 

 the nostrils are superior instead of lateral, and without 

 bristles ; the wing more falcate, and with ten primaries 

 instead of nine ; the tail with ten feathers instead of 

 twelve ; the feet are weaker, the hind toe more or less 

 versatile, and the anterior toes usually lack the normal 

 number of joints ; and there are peculiarities in their 

 vocal organs. 



The Genus Panyptila comprises Swifts which have the 

 legs thick, hind toe directed laterally, legs feathered to 

 the claws, second primary longest, and tail forked. 



The White-throated Swift, P. melanoleuca, Baird, of 



