242 
exhibit some of the strangest forms in the bird world, including crests, 
ruffs, fans, and muffs, exaggerated tails, long plumes, and enormous sword- 
like and fine awl-shaped bills, but their most striking feature is the brilliant 
metallic colorations that gleam on various parts of the body. They 
feed largely upon the nectar of flowers. The tongue is very long and 
protrusive as in the Woodpeckers, but with its sides curled over towards 
the middle to form a double tube frayed into a brush-like tip that makes a 
most efficient organ for sucking liquids. Numbers of small insects, how- 
ever, are taken with the nectar and, judging from feeding experiments on 
captives, seem to be necessary to the bird’s welfare. They are usually 
minute forms taken from the flowers from which the nectar is obtained. 
Hummingbirds as a group are tropical and subtropical species and 
increase greatly in number to the south, though two species range well to 
the north. 
FAMILY — TKOCHILIDAE. HUMMINGBIRDS 
There is only one family of Hummingbirds, represented in eastern 
Canada by a single species, in the far west by three. 
Very minute birds, 3-75 inches or less in length, with long, spine- 
shaped bill (Figure 245), and brilliant metallic colours. 
428. Ruby- throated Hummingbird. Archilochus colubris. L, 3*74. Plate 
XXXIX A. Male: rich, metallic, bronzy-green above and on flanks. Below, dull white 
__ with throat patch of scintillating ruby red. Female and juvenile 
alike, green above, with white throat slightly streaked with 
— ' ' ' ' greyish or showing a few sparse spots of brilliant ruby. 
Distinctions. To be mistaken in western Alberta only for 
Figure 245 the Rufous Hummingbird, Plate XXXIX B. The male with 
Hummingbird; natural its brilliant green, instead of unmetallic brick red, back is 
size. easily identified. Females and juveniles of the two species are 
more alike, but the green back in this species is always bright 
and complete; that of the Rufous is duller and has always considerable rufous suffusion 
on the flanks, below, and especially on the base of the tail. 
Field Marks. Small size and buzzing, insect-like flight. Except in western Alberta, 
the only Hummingbird to be expected in the Prairie Provinces. The green back and gleam- 
ing ruby throat in the male, and the green back and lack of rufous suffusion in other plum- 
ages. 
Nesting. In a beautiful structure, covered with bits of lichen cemented together with 
cobweb, saddled on the top of a branch. 
Distribution. Eastern North America. In Canada, west to Alberta, and probably 
to the foothills. The Hummingbirds of Alberta have not been carefully identified. 
Hummingbirds fly forwards, backwards, sideways, or remain perfectly 
stationary in the air with equal ease — another instance of parallel develop- 
ment — a bird flying like an insect yet in structure strictly bird-like. The 
wings vibrate with a rapidity that can be measured only by the tuning- 
fork method used with insects. This system of flight is fundamentally 
different in method from that of other birds and consequently the wings 
differ from the usual type. They are long, narrow, and non-flexible, and the 
keel of the sternum is immensely deepened to give support to the great 
muscles that move them. In proportion to its wing-spread a Humming- 
bird has a breast keel nearly three times larger than that of a Pigeon, a bird 
of average flight, or forty times larger than that of an Albatross. 
Economic Status. When it is remembered that some of the smallest 
insect pests are the most destructive, we can realize that possibly the 
economic importance of the Hummingbird may be greater than suspected. 
