LIST AND DESCRIPTION 99 



425. White-throated Swift (Aeronautes melanoleucus.) 



Common summer resident in the badlands of South Da- 

 kota. Larger than the Chimney Swift. Above and sides green- 

 ish black; throat, belly and flanks white. Tail slightly forked. 

 Nests in holes in inaccessible sides of cliffs. 



FAMILY TROCHILID^. HUMMINGBIRDS 



Hummingbirds are the smallest of all the birds and, as far 

 as we know, only one species visits South Dakota long enough 

 to raise one brood of young; after which it departs for tropical 

 regions. 



This exquisite species gathers its food from the flowers 

 of our gardens, but must be carefully distinguished from equally 

 large moths which gather their food in the same way, poising on 

 wing before flowers in hummingbird fashion. 



428. Ruby-throated Hummingbird (Archilochus colubris.) 



The smallest and one of the most beautiful of our birds. 

 About three and one half inches in length. The male above is 

 a glossy golden green; belly grayish and throat ruby. Tail 

 forked. In the female the throat is gray, and the tail is not so 

 prominently forked. 



Breeds occasionally over the State. The nest is fastened 

 to the top side of a horizontal limb and consists of downy ma- 

 terial supported on the outside by lichens, which are apparently 

 glued on by saliva which the bird secretes, or by some gummy 

 substance gathered by the builder. Two white eggs are de- 

 posited. 



FAMILY TYRANNID^E. FLYCATCHERS 



The Flycatchers are named for their habit of catching 

 insects on the wing. This is their regular way of securing food. 

 They do not fly continuo'usly however, like Swallows and Swifts, 

 but dart out upon their prey from some perch, usually a dead 

 limb or telephone wire. They are all summer residents and do 

 not arrive in the spring until numerous flies are on the wing. 

 They have broad bills and bristled mouths like all fly-catching 

 birds. A number of the smaller ones are so similar in size and 



