FAM. XX. SWIFTS 167 



notched, of rounded, white-tipped feathers. This bird is seen 

 by most people only when hovering over flowers in search of 

 food, and is hence thought to be always on the wing. If care- 

 fully watched, it will often be seen at rest on the twigs of 

 tree tops. The only living forms which may be mistaken for 

 hummingbirds are insects called hawk or sphinx moths. Most 

 of these are found hovering over flowers in the evening; the 

 hummingbirds visit the flowers in the daytime. 



Length, 3; wing, 1| (H-l|) ; tail, li ; culinen, f. North America 

 from the Plains eastward ; breeding from Florida to Labrador, and win- 

 tering in Cuba, eastern Mexico to Central America. Rieffer's Humming- 

 bird (4-38. Amaz'iUa fuscicaudata) of southern Texas to northern South 

 America is a brilliant green hummingbird, with dark purplish wings and 

 deep chestnut tail; the belly is gra\'. Length, 4; wing, 2\ ; tail, 1| ; 

 culmen, |. The Buff-bellied Hummingbird (439. Amazilia cerviniventris) 

 of southern Texas to Central America is a similar green bird, with the 

 belly pale cinnamon color. Length, 4'^; wing, 2\ ; tail, H; culmen, |. 



FAMILY XX. SWIFTS (MICROPODID^E) 



A family (75 species) of long-winged, close-feathered, small- 

 bodied birds, with large, swallow-like or nighthawk-like mouths, 

 and almost unri- 

 valed power of 

 flight. Almost the 

 whole day is spent 

 on the wing, catch- 

 ing enormous num- 

 bers of insects. 

 These birds are 

 found in immense 

 flocks, especially 

 when nesting o r 



roosting. Chimney Swift 



1. Chimney Swift (423. Chcetura peldgica). — An ashy-black 

 bird resembling the swallow, with very long wings and 

 short, rounded, spiny-tipped tail.^ In certain places 

 where large, unused chimneys are found, great flocks 



