554 The Roller-like Birds 



they have a prominent breast-bone which serves for the attachment of the power- 

 ful muscles moving the wings. Their feet are small and delicate, just sufficient 

 in fact to hold them up while perching; they rarely alight on the ground. 



Distribution. Hummingbirds are confined exclusively to the New World, 

 being most abundant among the northern Andes, and between the parallels 

 of ten degrees north and south of the equator, from which region they diminish 

 in numbers both to the northward and southward. Of the more than five hun- 

 dred species known, nearly two hundred are found in Colombia, over one hun- 

 dred in Ecuador, seventy in Central America, about fifty in Mexico, and only 

 seventeen in the United States, while about seven species reach the southern 

 extremity of South America. They appear to prefer mountainous countries, 

 where, within the tropics, the character of the earth's surface and the vegetation 

 may be widely different within relatively short distances. 



Of the Hummingbirds reaching the United States only one, the Ruby-throated 

 (Trochilus colubris), is found east of the Mississippi River. In summer it may 

 be found rearing its young from the Gulf of Mexico to Canada and west to the 

 Great Plains, while in winter it retires to southern Florida, Cuba, eastern Mexico, 

 and Central America. The Rufous Hummingbird (Selasphorus rufus) is found 

 in summer as far north as Prince William Sound, Alaska, and in winter along 

 the tablelands of Mexico. A number of species are found in the Rocky Mountain 

 area, but the larger number of those reaching the United States are really 

 Mexican or Central American species found just over the southwestern border. 



Nests and Eggs. The nests of Hummingbirds are marvels of bird archi- 

 tecture, and the discoverer of one may count himself fortunate. They are usually 

 deeply cup-shaped, and made of plant down fastened together with spiders' 

 webs, while the outside is often ornamented with lichens, mosses, and rarely 

 feathers. Usually they are saddled upon a limb and are hard to distinguish, 

 at a little distance, from a knot or projecting piece of bark. Some kinds, however, 

 as the Hermit Hummingbirds, fasten the nest to one side of a dfooping, green 

 leaf, and still others attach their nests to the sides of cliffs or overhanging rocks. 

 The eggs are almost invariably two, pure white and unspotted. 



Size. The nearest relatives of the Hummingbirds are, of course, the Swifts, 

 but otherwise there are none very closely allied to them in any part of the world. 

 While they are all small birds, there is still considerable range in size among 

 them, the largest being the Giant Hummer ( Patagona gigas), found in the higher 

 Andes, which is about eight and a half inches in length, while the smallest bird 

 known in the world is the Fairy Hummingbird, which is a native of Cuba, its 

 total length being only two and a quarter inches. For some time the Vervain 

 Hummingbird of Jamaica was supposed to be the smallest bird, but it is a 

 trifle larger than the Fairy. The nest is only about three quarters of an 

 inch in diameter across the cavity, and the tiny eggs a little over a quarter 

 of an inch long ! 



Bills. In the matter of the length and shape of the bill there is much differ- 

 ence among Hummingbirds. The shortest bill is hardly more than a quarter 

 of an inch long, while the longest is fully five inches in length, and is provided 



