450 NORTH AMERICAN BIRDS. 



in depth and 1.25 inches in breadth. It is of very homogeneous con- 

 struction, the niiiterial of which it is made being almost exchisively a sub- 

 stance of vegetable origin, resembling wool, coarse in fibre, but soft, warm, 

 and yielding, of a deep buff color. This is strengthened, on the outside, by 

 various small woody fibres ; the whole, on tlie outer surface, entirely and 

 compactly covered by a thatching of small lichens, a species of Parmelia. 



A nest obtained in Lynn, Mass., by Mi-. George 0. Welch, in June, 1860, 

 was built on a horizontal branch of an apple-tree. In measures 1.50 inches 

 in height, and 2.25 in its external diameter. The cavity is more shallow, 

 measuring .70 of an inch in depth and 1.00 in diameter. It is equally 

 homogeneous in its composition, being made of very similar materials. In 

 this case, however, the soft woolly material of which it is woven is finer in 

 fibre, softer and more silky, and of the purest white color. It is strength- 

 ened on the base with pieces of bark, and on the sides with fine vegetable 

 fibres. The whole nest is beautifully covered with a compact coating of 

 lichens, a species of Parmelia, but different from those of the Georgian nest. 



The fine silk-like substance of which the nest from Lynn is chiefly com- 

 posed is .supposed to be the soft down which appears on the young and 

 unexpanded leaves of the red-oak, immediately before their full develop- 

 ment. The buds of several of the oaks are fitted for a climate liable to 

 severe winters, by being protected by separate downy scales surrounding 

 each leaf. In Massachusetts the red-oak is an aljundant tree, expands its 

 leaves at a convenient season for the Hummiug-Bird, and these soft silky 

 scales which have fulfilled their mission of protection to the embryo leaves 

 are turned to a good account by our tiny and watchful architect. The spe- 

 cies in Georgia evidently make use of similar materials from one of the 

 southern oaks. 



The eggs measure .50 by .35 of an inch, and are of a pure dull white. 



Trochilus alexandri, Bourc. & Mulsant. 



BLACK-CHINNED HTJMMING-BIRD. 



Trochilus alexandri, Bourcier & Wulsant, Ann. ile la Soc. d'Agric. de Lyons;, IX, 1846, 

 330. — Heeemanx, Jour. A. N. Sc. Phila. 2d ser. II, 1S53, 269. —Cassis, 111. N. 

 Am. Birds, I, v, 1854, 141, pi. xxii. — Gould, Mon. Trochilids, xiv, Sept. 1857, 

 plate. — Baird, Birds N. Am. 1858, 133, pi. xliv, f. 3. — In. M. B. II, Birds, 6, pi. 

 V, f. 3. '- Heerm. X, S, 56. - Cooper, Orn. Cal. I, 1870, 353. 



Sp. Char. Very similar to Trochilus coluhris. Tail slightly forked ; the rhin and upper 

 part of the throat opaque velvety-black, without metallic reflections, which are confined 

 to the posterior border of the gorget, and are violet, .sometimes changing to steel blue or 

 green, instead of coppery-red. Female without the metallic .scales ; the tail-feathers 

 tipped with white; the tail graduated, not emarginated ; the innenno.st feather among the 

 longest. Length of male, 3.30; wing, 1.70; tail, 12G; bill, .75. 



Hab. Coast of California, southward, and east to the Wahsatch and Uintah Mountains, 

 Utah. 



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