BIHDS — TROCUILIDAE — SELASPIIORUS. 133 



TROCHILUS ALEXANDIU, Bourc. & Mulsant. 



Blnck-chinneil Iluininiii'^ Bird. 



TVocAi/uj alexandri, BomciER k Mri.sAXT, Ann. <lc la Soc. li'Agric. de Lyonii, IX, 1R4G, 330. — IIeermakm, Jour. A. 

 N. Sc. Phila. ad ser. II, 1853, 2C9.— Cassis-, 111. N. Am. Birds, I, v, 1854, 141 ; pi. xxli.— Gould, 

 Mun. Trochilidaa, xir, Sep. 1857. Plate. 



8r. Cii. — Very similar lo Trochilus calubris. Tail slightly forked; the chin 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, 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 emarginat d ; the innermost 

 feather among the longest. Length of male 3.30 ; wing 1.70 ; tail 1.2G ; bill .75. 



Hob. — Coast of California, soutliward. 



This species is very similar in color to the common ruby-throated humming bird of the 

 eastern United States, and represents it on the west coast. Tlie upper parts and sides are of the 

 same metallic golden green, the gorget of much the same extent, bordered behind by whitish, 

 which (less pure) extends alon^ the middle of the belly, and involving the crissum, the leathers 

 of which are greenish in the cei.tre. There is the same white spot behind the eye. T. alexandri 

 is, however, rather the larger ol the two ; the bill nearly one-tenth of an inch longer. The tail 

 is much less deeply forked, in fact the outer feather is a little shorter than the second, and the 

 innermost broad green one only about .10 of an inch shorter than the longest, instead of 

 about .30. There is a tinge of metallic green to the tips of the tail feathers much less distinct 

 in T. coluhris. The whitish collar behind the metallic feathers of the throat, usually considered 

 as a specific character, I find to be shared almost equally well by T. colubris. The chief distinc- 

 tions between the two species are to be found in the violet steel blue or steel green reflections of 

 the hinder part of the gorget, varying with the situation of the featliers and the specimen, as 

 distinguished from the bright fiery or coppery red of the other. The chin and upper part of 

 the throat extending beneath the eyes are opaque velvety or greenish black, without metallic 

 lustre, while in T. colubris it is only the extreme chin which is thus dull in appearance. 



It is exceedingly difficult to distinguish the female of this species from that of T. colubris. 

 The size is rather larger, and the tail rounded, without any emargination ; the middle feathers 

 being .15 of an inch longer than the lateral ones, instead of actually shorter. The color is 

 much the same. 



In both species the outer tail eathers, though broader than in the male, are quite acutely 

 pointed on the terminal third, one side or the other of which is slightly concave, instead of 

 being linear to near the end, and rounded without any concavity, as in Selasphorus and Atthis. 



The preceding description of this species is taken from specimens belonging to the very 

 extensive collection of birds of the vicinity of Fort Tejon, made by Mr. John Xantus de Vesey. 



SELASPHORUS, Swain son. 



Stlasphonu, Swaihsok, Faun. Bor. Amer. II, 1831. 



After separating the North American species usually called Selasphorus, with red metallic 

 scales on the crown, and the outer primary not attenuated at the top, there remainbut two belong- 

 ing to the restricted genus. Even in these there are some difi'erences of form, but they may be 

 considered in the present instance as specific characters. 



