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 TROCHILIDZ. 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. RupBy-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. 
BAMIEY “TY RANNIDA, 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 continuously 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 
