Iv HUMMING-BIRDS 313 
and of habits ; so that they have to be classed in more than a 
hundred distinct genera or systematic groups of species, these 
genera being really as unlike each other as stonechats and 
nightingales, or as partridges and blackcocks. The figures we 
have quoted, as showing the proportion of birds in general to 
humming-birds, thus represent real facts; and they teach us 
that these small and in some respects insignificant birds con- 
stitute an important item in the animal life of the globe. 
Humming-birds are, in many respects, unusually interesting 
and instructive. They are highly peculiar in form, in struc- 
ture, and in habits, and are quite unrivalled as regards variety 
and beauty. Though the name is familiar to every one, few 
but naturalists are acquainted with the many curious facts in 
their history, or know how much material they afford for 
admiration and study. It is proposed, therefore, to give a 
brief and popular account of the form, structure, habits, dis- 
tribution, and affinities of this remarkable family of birds, as 
illustrative of the teeming luxuriance of tropical nature, and 
as throwing light on some of the most interesting problems of 
natural history. 
Structure 
The humming-birds form one compact family named 
Trochilide. They are all small birds, the largest known being 
about the size of a swallow, while the smallest are minute 
creatures, whose bodies are hardly larger than a humble-bee. 
Their distinguishing features are excessively short legs and 
feet, very long and pointed wings, a long and slender bill, 
and a long extensible tubular tongue; and these characters are 
found combined in no other birds. The feet are exceedingly 
small and delicate, often beautifully tufted with down, and so 
short as to be hardly visible beyond the plumage. The toes 
are placed as in most birds, three in front and one behind, 
-and have very strong and sharply curved claws; and the feet 
serve probably to cling to a perch rather than to give any 
movement to the body. The wings are long and narrow, but 
strongly formed ; and the first quill is the longest, a peculiarity 
found in hardly any other birds but a few of the swifts. The 
bill varies greatly in length, but is always long, slender, and 
pointed, the upper mandible being the widest and lapping 
