BIRDS — TROCHILIDAE. 129 



Family TROCHILIDAE- The Humming Birds. 



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 con- 

 tinent and islands of America, and are most abundant in the Central American States, though 

 single species range almost to the Arctic regions on the north and to PatagOnia on the south, 

 as well as from the seacoast to the frozen summits of the Andes. The number of known species 

 considerably exceeds 300, and new ones are being constantly brought to light ; so that an 

 estimate of 400 species is, perhaps, not too large. Many are very limited in their range ; some 

 confined to particular islands, even though of small dimensions. 



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 exca- 

 vated to the tip for the lodgment of the tongue, and form a tube by the close apposition of their 

 cutting edges. There is no indication of stiif bristly feathers at the base of the mouth. The 

 tongue has some resemblance to that of the woodpeckers 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 into flowers of various shapes without 

 opening the bill very wide. 



The wings of the humming birds are long and falcate ; the shafts very strong ; the primaries 

 usually ten in number, the first always longest ; there are six secondaries. The tail has but 

 ten feathers. The feet are small ; the claws very sharp and strong. ^ 



The species now known to inhabit the United States, though few, are yet nearly twice as 

 many as given by Mr. Audubon. It is probable that additional ones will hereafter be detected, 

 particularly on our southern borders. 



The different authors who have made a speciality of the humming birds have named a great 

 many sub-families and genera, but there has as yet been no published systematic description of 

 the higher groups. It is probable that the North American species belong to two different 

 sub- families — the LampornitJiinae and the Trochilinae — and to at least four genera ; but the 

 precise character and limits of these I am unable to give. The following remarks, however, 

 may serve to sketch out the characters of the North American species : 



A. Edges of mandible serrated near the end. Throat without metallic scale-like feathers. 



Lampornis. — Bill depressed, slightly curved. Tail broad, slightly emarginate ; the 

 outer feather as broad as the rest. Wings reaching the tip of tail. No metallic 

 feathers on the throat. 



B. Edges of mandible nearly even towards the tip, without distinct serrations. Throat with 

 metallic scale-like feathers. 



Trochilus. — Feathers of throat but little elongated laterally. Lateral tail feathers but 

 little narrower than the others, and lanceolate acute. Tail forked. 



^Most of the above general remarks are borrowed from Burmeister, (Thiere Brasiliens, Vogel, 311,) to which I would refer 

 for an excellent article on tho structure and habits of humming birds. 



17 b 



