INSTINCT AND INTELLIGENCE IN BIRDS rey 
crow in Egypt and India, where from a long and undisturbed inter- 
course with man, it has come to build its nests in the city streets, and 
in Cairo even before the foliage of the lebbek trees is out, often gives 
free rein to this propensity, as was well shown by the experience of an 
optician in Bombay, who lost a large store of steel spectacle-frames, 
and later found them in a ruined state, worked into a nest of this 
familiar bird. The propensity to seize bright objects, and to hide and 
store food by burying it in the ground, a practise attributed to the 
European crow, raven, magpie and rook, is undoubtedly instinctive in 
origin. Their ability to find it again would depend more upon intelli- 
gence than in the dog, which has the same tendency, for they are pre- 
sumably without the guiding power of scent. The Californian wood- 
pecker (Melanerpes formicivorus) is noted for the autumnal stores of 
acorns which it embeds in the bark of trees, but the strong instinctive 
impulse which shapes its conduct is accentuated by the reported fact 
that the holes so nicely. drilled are occasionally filled up with stones. 
That color plays an important part in the lives of birds seems highly 
improbable, although it is a commonplace fact that the nest in many 
cases harmonizes perfectly with its surroundings. For several seasons 
I made a practise of offering colored yarns, such as blue, brown, green 
and bright red, to various species of birds, for building purposes, and 
especially to robins and cedar waxwings; as a rule, all colors were taken 
indiscriminately, with very bizarre nests as a result. When white 
threads or long streamers of cotton cloth were added, these were usually 
taken first, and in greater quantity, apparently because they were more 
conspicuous, and sometimes to the detriment of the builders. Thus, 
one of the least flycatchers took and dropped so much of the cloth that 
a white trail was finally laid from field to nest, in the construction of 
which five times more was used than needed. ‘The quaint structure 
which resulted was too obvious to escape destruction, and it did not 
endure many hours. 
The docility of birds is well illustrated by the trainer’s power over 
many species, and by the tricks which, through a system of rewards 
and punishments, they can be made to perform. A classical illustra- 
tion is furnished by the art of falconry, the popular sport of middle-age 
Europe, in which the young of the wild peregrine falcon, or of some 
other hawk, was trained to limit its instinct to kill to a particular kind 
of game, to follow the falconer afield, to stoop to the quarry, and return 
to its master’s call. After a similar fashion the instincts of the cor- 
morant have been molded to the will of man, and successfully used in 
taking fish, a practise which I am informed may still be witnessed in 
certain remote fishing communities in Japan, the trained birds descend- 
ing from father to son. 
Modern experiments in the laboratory, which have been conducted 
VoL. LXxviI.—10. 
