ORNITHOLOGY. 15 



by the winds. And the nest of the topaz-crested humming-bird, about seven-eighths of 

 an inch in diameter, is composed of the same materials, stuck over with lichens on the 

 outside, and- firmly fixed in the hanging cleft of some strong creeper by threads of a 

 cottony substance, and very slender roots or tendrils, the whole lower part as if cemented 

 by a thin coat of glue. 



Most writers agree in the fact, that humming-birds lay only two eggs, but the 

 trochilus hirsutus lays only one. This small fecundity, with the many casualties 

 which are liable to destroy them, the vicissitudes of season, and the assaults of vari- 

 ous animals, birds, and even insects, will give us some idea in what immense profu- 

 sion these little birds exist, when two, or at most four, is the number of young reared 

 in a season. 



The eggs are not so small in proportion as one would imagine on looking at the 

 bird. That of the topaz-crested humming-bird is nearly five-eighths of an inch in 

 length, and about three-eighths in diameter. In shape they are nearly a complete 

 oval, and of a pure and delicate white. The period of incubation is remarkably short j 

 the black humming-bird sits twelve days, and the young leave the nest and follow 

 their parents in eighteen days j and the North American species, according to 

 Audubon, hatches only ten days, and the young are ready to fly in one week. 



The desire to possess creatures of such beauty in a tame state, has induced persons 

 often to try the experiment of keeping them in cages, though yet comparatively 

 without success. 



When we examine attentively the structure of any bird, we soon come to the con- 

 clusion that the most important parts of its outward form are those organs which 

 serve for the means of transporting it from place to place. On presenting a hum- 

 ming-bird to the most common observer, the first exclamation generally is, " What a 

 beautiful little creature !" The second, " But what large wings it has !" Such, indeed, 

 is the case, and in most instances the size of the wings and strength of their quills 

 are entirely out of proportion to our ideas of symmetry in a creature clothed with 

 feathers ; but, upon comparing them with its necessities, and the other parts of its 

 frame, their utility and design become obvious. All their other parts, not called into 

 action during flight, are very slender, almost frail ; their tarsi are short, and the feet 

 small, so as riot to incommode during flight, while they point out an inability for any 

 long support or assistance in procuring sustenance, by climbing or hanging in various 

 positions, as we see employed by the titmice, and many of the slender-billed warblers. 

 Their food is derived from the sweet nectar of flowers, or from insects which must 

 either be taken in a rapid flight, or withdrawn from the deep tube, or cup-shaped re- 

 cess of blossoms which grow and hang in every direction, and which it would be 

 impossible to reach unless by suspension above or under. Another great necessity for 

 their possessing organs of such power, is to enable them to pass in safety through the 

 migrations, and the long flights which are sometimes necessary for their preservation, 

 and during which they have often to withstand a passing gale, showers, or even the 

 rigor of a snow-storm. The beautiful climes where we have seen they inhabit, are at 

 seasons subject to perpetual rains, which drench and almost inundate their abodes, or 

 to hurricanes that in a few minutes leave only a wreck of all that was before so mag- 

 nificent and luxuriant ; and they pass by these means before the dangerous season, to 

 districts where the reparation of a previous wreck is proceeding with all the magical 

 rapidity of tropical vegetation. 



The wings in general exceed the tail in length, unless when that member is extra* 

 3 



