XV1ll THE STORY OF THE BIRDS. 
matic. Color calls usually white and mostly visible from the 
rear; often concealed except in flight, depending on motion for 
display ; often ornamental. Doubtless brilliant colors and orna- 
ments may answer the same purpose. Whirring flight, wing 
strokes, and vocal cries as substitutes. Brotherly affection among 
birds. 
For Study.—Note white wing bars of English sparrows, jays, 
ete., and the whirring flight of many flocking birds. Observe the 
little by-talks of small chickens as they run and feed. 
CuapTrerR XI.—The weapons of the primitive birds were pre- 
eminently their teeth, which were lost, perhaps, because of changed 
habits induced by flight. Early weapons useful more especially 
in prey taking. Special weapons were developed in fighting ri- 
vals. Wing spur the earliest of these, perhaps; leg spur later, 
and confined mostly to one group. Birds’ weapons not orna- 
mented, but probably have given way to other forms of emula- 
tion, as song, antics, etc. Battle is often mere bluff, chasing, 
inflation, etc. Birds have no shields. Weapons a means of ad- 
vancing the race. 
For Study.—Note armament of chickens, turkeys, and various 
birds of prey. Compare pictures of the sheep and antelopes, and 
see the curved and lyrated forms full of the curves of beauty. 
Note.—There is no such thing as a poison beak or gland 
among the birds, newspaper paragraphs to the contrary notwith- 
standing. 
Cuaprer XII.—The play of birds sometimes seems humorous 
purely, but it usually has the purpose of charming or displaying 
pretty parts. Instances noted. Females often play back, not al- 
ways. Some antics take the form of ecstasies. 
Odor has no special glands among birds as among mammals 
and reptiles, with one exception; but odors are evidently quite 
distinctive, and doubtless have purpose in them in some Cases, 
Some birds smell keenly, but vultures hunt largely by sight. 
Mud probers use smell in searching, but some other forms have 
no nostrils. 
For Study.—Note little chickens’ mock fights, crows tumbling 
in flight, turkeys strutting, pigeons pouting, house sparrows whir- 
ling, ete. Note incidental odors of fish eaters. Put the hand in 
a laying Guinea-hen’s nest and see if she abandons it. 
