Two specimens of this species obtained in Mexico by M. de Saussure are in the collection of Dr. Sclater.
Mr. Ridgway saw on the Truckee River, near Pyramid Lake, in May, 1868, what he supposes to have been this species. It was not common, only a few individuals being observed every evening just before dusk, flying overhead exactly in the manner of Chimney Swallows (C. pelagica), which they also exactly resembled in appearance. They flew so high that specimens could not be obtained. They were entirely silent, and appeared at no other time than in the evening, in these respects differing strikingly from the eastern species.
Family TROCHILIDÆ.—The Humming-Birds.
Char. Least of all birds; sternum very deep; bill subulate, and generally longer than the head, straight, arched, or upcurved. Tongue composed of two lengthened cylindrical united tubes, capable of great protrusion, and bifid at tip; nostrils basal, linear, and covered by an operculum; wings lengthened, pointed; first quill usually longest except in Aithurus, where it is the second; primaries, 10; secondaries, 6; tail of ten feathers. Tarsi and feet very diminutive, claws very sharp. (Gould.)
There is no group of birds so interesting to the ornithologist or to the casual observer as the Humming-Birds, at once the smallest in size, the most gorgeously beautiful in color, and almost the most abundant in species, of any single family of birds. They are strictly confined to the continent and islands of America, and are most abundant in the Central American and Andean States, though single species range almost to the Arctic regions on the north and to Patagonia on the south, as well as from the sea-coast to the frozen summits of the Andes. Many are very limited in their range; some confined to particular islands, even though of small dimensions, or to the summits of certain mountain-peaks.
The bill of the Humming-Bird is awl-shaped or subulate; thin, and sharp-pointed; straight or curved; sometimes as long as the head, sometimes much longer. The mandibles are excavated to the tip for the lodgement of the tongue, and form a tube by the close apposition of their cutting edges. There is no indication of stiff bristly feathers at the base of the mouth. The tongue has some resemblance to that of the Woodpecker in the elongation of the cornua backwards, so as to pass round the back of the skull, and then anteriorly to the base of the bill. The tongue itself is of very peculiar structure, consisting anteriorly of two hollow threads closed at the ends and united behind. The food of the Humming-Bird consists almost entirely of insects, which are captured by protruding the tongue in flowers of various shapes without opening the bill very wide.
The genera of Humming-Birds are very difficult to define. This is partly owing to the great number of the species, of which nearly four hundred and fifty have been recognized by authors, all of them with but few exceptions diminutive in size and almost requiring a lens for their critical examination, so that characters for generic separation, distinct enough in other families, are here overlooked or not fully appreciated. A still greater difficulty, perhaps, is the great difference in form, especially of the tail, between the male and female, the young male occupying an intermediate position. The coloration, too, is almost always very different with sex and age, and usually any generic characters derived from features other than those of bill, feet, and wing do not apply to the females at all.
In the large number of species of Humming-Birds arranged in about one
hundred and thirty genera, only two subfamilies have been recognized, as follows:—