numbers of insects, but its chief work is picking up and — 
cracking small seeds and grains. This bill, therefore, has © 
developed into an irregular cone-shaped tool, with a fine 
front point and sharp edges, which the strong jaws and — 
nimble tongue use to work off the outer husks or shells of 
their chosen dainties. 
; Consequently, a bird student: ni always look at the 
size and shape of a bird’s bill to help him determine the © 
name of a new acquaintance, and keep a notebook record of 
all he has time to see in the fleeting glimpses he gets of a 
bird, for later identification through bird books. 
Sparrows spend much of their time on the ground or | 
among low shrubbery, while swallows use the air for a place 
in which they play or work most of their waking time, which _ 
means from early dawn until night falls, usually. This 
- different habit of living has made a great change in the size © 
and shape of their wings, for when a living organ is often © 
used it is apt to excel one that is not. A sparrow has, 
generally, short, rounded wings, and a swallow has long 
wide ones which bear him through the sky in a way that 
- children, dreamers, and aviators envy. The swallows sweep 
through the air, dipping up and down, soaring high or low, 
as they follow the whims of insect life, until the watcher 
with a pair of opera glasses, grows dizzy, as he tries to 
decide which particular species is whirling about him; while 
sparrows take short, more or less jerky, flights unless 
they are species having a period of setae when they 
may travel great distances. 
Both kinds of birds vary in size from the five “inches 
of a willow goldfinch or a northern violet-green swallow, 
to the eight inches of a towhee or a martin; while in color 
the sparrows may be black, brown, gray, reddish, or yellow _ 
and the swallows are apt to have changeable blacks, blues, 
browns, greens, or purples. To add to the puzzle some birds, 
like the male western goldfinch, wear a brilliant yellow and 
black coat in the summer, which changes to a brownish- 
et 
