146 
This is an interesting species, swallow-like in outward appearance and 
food-hunting habits yet structurally distinct from the Swallows. It is an 
odd example of parallel development of widely separated characters induced 
by similarity of requirement. Its habits have entirely changed since the 
advent of the white man and, forsaking hollow trees, it is now practically 
dependent upon chimneys for sites in which to build its nest. The winter 
home of the Chimney Swift is unknown. The mystery, however, should 
not be exaggerated, as there are numbers of Swifts in the western hemisphere 
looking very like this one and the bird has probably been overlooked in its 
winter quarters or confused with closely allied forms. The Swift spends 
much time on the wing and seldom comes to rest except in a chimney or 
hollow tree. In the autumn, before migration, great numbers gather to- 
together and at evening seek the shelter of some ample chimney where 
they pass the night. They may be seen just before dusk flying about in 
complicated patterns near the chosen chimney, and as the sun sets, circling, 
until as they throw the wings straight up over the back and drop fluttering 
into the stack, one rapidly following another, they appear to pour in like a 
miniature maelstrom. The birds cling to the perpendicular walls of the 
chimney by hundreds, in masses like lumps of soot. Occasionally one with 
insecure hold drops a few feet, loosening as it does so, others below; there 
is a momentary flutter of wings and a small chorus of fine sharp chippings 
until they find new holdings and settle for the night. 
SUBORDER—TROCHILI. HUMMINGBIRDS. 
These tiny, insect-like birds with brilliant flower-like coloration, 
unbird-like flight, and wonderfully varied form, are a typically American 
order. In a way, they occupy much the same position in the New World 
as the Sun Birds do in the Old World, but the similarity between the two is 
superficial and not one of relationship. Many species are highly specialized 
and 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 on various parts of the body, that gleam in the sun. They 
feed largely upon the nectar of flowers. The tongue is very long and 
protrusive as in the Woodpeckers, with its sides curled over towards the 
middle to form a double tube frayed into a brush-like tip which makes a 
most efficient organ for sucking liquids. Numbers of small insects, however, 
are taken with the nectar and, from feeding experiments on captives, they 
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 one species in the east 
ranges well to the north. 
FAMILY—TROCHILIDH. HUMMINGBIRDS. 
As there is only one family of Hummingbirds, represented in eastern 
Canada by a single species, see preceding and succeeding headings for des- 
eription. 
428. Ruby-throated Hummingbird. rr.—LkE COLIBRI A GEORGES RUBIS. Archilo- 
chus colubris. L, 3-74. Plate XXII A. 
