I had occasion in a note published several years ago in the _Revue
Scientifique_ to mention a parroquet which I have since continued to
observe, the manifestations of whose intelligence are both interesting
and instructive. Many acts of birds are difficult of interpretation.
To speak only of their songs, the meanings of most of the innumerable
varieties of sounds which they produce, and of their diverse
warblings, escape us completely. It is not possible to find the
meaning of these things except by forming suppositions and hypotheses,
or by catching the connections between cries and acts. But instances
of the latter kind are extremely rare in comparison with the great
majority of the manifestations made by animals.

Thus, to select examples which every one can observe, when a canary
bird is warbling in its cage and becomes deafening, or when a lark
rises straight up in the air and _incantat suum tirile tirile_--sings
its _tirile tirile_--as Linnæus picturesquely expresses it; when a
tomtit, leaping from branch to branch of a willow or among the reeds,
repeats its florid warblings; when a raven croaks; when a blackbird
whistles--what significance can we attach to their songs and their
cries? Certainty is impossible, and we can only form more or less
plausible hypotheses concerning the interpretation of them.

The parrot furnishes us one more aid in this matter than other birds,
and this helps us, to a certain extent, in overcoming the difficulty
of interpretation. It has an articulate voice, and when we have taught
it a few words, the meaning which it gives them may be better divined
by us according to the tone and the rapidity or slowness of its
utterance. This permits us to discover the feelings that move it, for