Iv HUMMING-BIRDS 315 
iridescent, refulgent, celestial, glittering, shining, are con- 
stantly used to name or describe the different species. 
No less remarkable than the colours are the varied develop- 
ments of plumage with which these birds are adorned. The 
head is often crested in a variety of ways; either a simple 
flat. crest, or with radiating feathers, or diverging into two 
horns, or spreading laterally like wings, or erect and bushy, 
or recurved and pointed like that of a plover. The throat 
and breast are usually adorned with broad scale-like feathers, 
or these diverge into a tippet, or send out pointed collars, or 
elegant frills of long and narrow plumes tipped with metallic 
spots of various colours. But the tail is even a more varied 
and beautiful ornament, either short and rounded, but pure 
white or some other strongly contrasted tint; or with short 
pointed feathers forming a star; or with the three outer 
feathers on each side long and tapering to a point; or larger, 
and either square or round, or deeply forked or acutely 
pointed ; or with the two middle feathers excessively long 
and narrow; or with the tail very long and deeply forked, 
with broad and richly-coloured feathers; or with the two 
outer feathers wire-like and having broad spoon-shaped tips. 
All these ornaments, whether of the head, neck, breast, or 
tail, are invariably coloured in some effective or brilliant 
manner, and often contrast strikingly with the rest of the 
plumage. Again, these colours often vary in tint according 
to the direction in which they are seen. In some species they 
must be looked at from above, in others from below ; in some 
from the front, in others from behind, in order to catch the full 
glow of the metallic lustre ; hence, when the birds are seen in 
their native haunts, the colours come and go and change with 
their motions, so as to produce a startling and beautiful effect. 
The bill differs greatly in length and shape, being either 
straight or gently curved, in some species bent like a sickle, 
in others turned up like the bill of the avoset. It is usually 
long and slender, but in one group is so enormously developed 
that it is nearly the same length as the rest of the bird. The 
legs, usually little seen, are in some groups adorned with 
globular tufts of white, brown, or black down, a peculiarity 
possessed by no other birds. The reader will now be in a 
position to understand how the four hundred species of 
