238 
Through the day time, the Nighthawk seeks such shade as may be 
available, but evidently coolness is not a necessity to it. The writer 
remembers one stifling day in the arid lands of southern Saskatchewan 
when although the breeze made by the travelling car struck like a furnace 
blast instead of giving refreshment, yet for some distance along the prairie 
road every fence-post had a dozing Nighthawk upon it, absorbing in sleepy 
content the intense heat of the mid-day sun that was shrivelling the 
surrounding vegetation. 
Economic Status. Of few birds can more good or less harm be told 
than of the Nighthawk. Its food, wholly of insects, is taken on the wing, 
high in the air where many of the insects are mating and at a time when 
their destruction does the most good. It is a surprisingly small bird when 
stripped of its thick coat of soft feathers, but requires a great amount of 
food. A list of the species taken by it includes great numbers of ants, 
June bugs, squash beetles, chinch bugs, leaf-hoppers, and other obnoxious 
species. The habit, common in some places, of using this bird as a live 
target for gunners when practising, is inexcusable and those guilty of it 
should be rigorously prosecuted. It should be realized that every offence 
against the laws protecting insect-eating birds is something more than a 
technical offence against an impersonal state; it is a direct blow at the 
welfare of the whole community. 
SUBORDER— CYPSELI. SWIFTS 
A widely spread suborder consisting of one family. 
FAMILY — MICROPODIDAE. SWIFTS 
Mostly small birds in dull colours without much pattern or variegation. 
Usually, over-all colours of sooty or black. Bill very small with large gape. 
Feet weak and fleshy rather than scaled (Figure 244 a and b). In general, 
resembling Swallows, in detail more like the Goatsuckers, but without the 
finely patterned plumages, and the feathers hard and compact rather than 
soft and full. The primaries very long, bowed, and extending when 
closed far beyond the tail (Figure 244 d). It is a group of birds super- 
ficially resembling Swallows, but structurally quite different from them, 
the similarity being brought about by common requirements and not by 
relationship. The compactly, hard-feathered wings, the long, bowed 
primaries, short secondaries, and the peculiar wing action of the Swifts are 
different from those of the Swallows. The Swallow beats the air with long, 
rythmical strokes, the Swift buzzes through it like a beetle and then sails 
on stiff-set wings locked into an even bow (Figure 244 e). The Swallow 
glides up and down invisible aerial w r aves like a sailboat, the Swift bores 
through them like a torpedo. The Swifts are noted for the extraordinary 
development of the salivary glands that produce an abundant secretion 
with which the nest of sticks is cemented together and to its perpen- 
dicular support. It is this cement that forms the edible bird’s nests of 
Chinese epicures. 
The Swifts live entirely on insects, catching their food on the wing. 
The North American Swifts are divided into two subfamilies. 
