192 LIFE HISTORIES OF NORTH AMERICAN BIRDS. 



entirely of fine mosses, the whole evenly quilted together into a smooth, homo- 

 geneous mass, and bound firmly together with silk from cocoons and spiders' 

 webs. It is saddled in a tripronged fork of a small 'twig, the three stems being 

 incorporated in the walls of the nest, holding it firmly in position, the main stem 

 being only one-twelfth of an inch in diameter. It measures 2| inches in outer 

 diameter by 3 inches in depth; the inner cup is 1J inches in diameter by three- 

 fourths of an inch deep. The walls of the nest are three-fourths of an inch 

 thick, and the inner cup appears very small for the large size of the nest. It 

 looks like a warrn and cozy structure, and it needs to be so. As the eggs were 

 only slightly incubated when found, the young would probably have hatched 

 by September 20, and would scarcely have been large enough to leave the nest 

 before October 12, by which time one might reasonably look for snowstorms at 

 such an altitude. There is but very little inner lining, not enough to hide the 

 moss, which looks to me like the down from willow catkins. Two eggs are laid 

 to a set, and probably two broods are raised in a season. 



The single egg before me is elliptical oval in shape, dull white in color. 

 The shell is close-grained and shows no luster. It measures 16.26 by 9.91 

 millimetres, or 0.64 by 0.39 inch. As there is but a trifling difference in the size 

 of most of our Hummingbirds' eggs, and apparently none in their shape and 

 color, I have, therefore, only figured the egg of a single species. 



The type specimen, No. 26332 (not figured), was taken by Mr. E. W. Nelson 

 on September 9, 1893, as already described. 



68. Trochilus colubris Linn^us. 



RUBY-THROATED HUMMINGBIRD. 



Trochilus colubris LiNN^US, Systema Naturae, ed. 10, I, 1758, 120. 

 (B 101, O 275, R 335, C 409, U 428.) 



Geographical range: Eastern North America ; north in the more southern parts 

 of the Dominion of Canada to about latitude 52°, in the interior in the Northwest Territory 

 to about latitude 57° and probably still farther ; west iu the United States to eastern North 

 and South Dakota, eastern Nebraska and Kansas, the Indian Territory and Texas; south 

 in winter to the West India Islands and through eastern Mexico to Veragua, Central 

 America. Casually to Labrador. 



The Ruby-throated or Northern Hummingbird, the sole representative of 

 this family in eastern North America, is only a summer visitor in the Dominion 

 of Canada and throughout the greater part of its range in the United States, except- 

 ing the southern portions of the Florida peninsula, where it winters to some 

 extent. By far the greater number of these birds, however, migrate farther south, 

 spending the winter in some of the West India Islands, while others pass 

 through eastern Mexico into Central America, as far south as Veragua. It 

 usually arrives along our southern border in the latter part of March, and 

 moves leisurely northward, rarely reaching the more northern States before 

 the middle of May, or about the time the early and hardier flowers begin to 



