he saw me on the inside of a large plate-glass window,
and seemed in doubt whether or not it was an image. Another of my
infants, a little girl, was not nearly so acute, and seemed quite
perplexed at the image of a person in a mirror approaching her from
behind. The higher apes which I tried with a small looking-glass
behaved differently. They placed their hands behind the glass, and
in doing so showed their sense; but, far from taking pleasure in
looking at themselves, they got angry and would look no more." The
first-mentioned child, at the age of not quite nine months,
associated his own name with his image in the looking-glass, and
when called by name would turn toward the glass even when at some
distance from it. He gave to "Ah!" which he used at first when
recognizing any person or his own image in a mirror, an exclamatory
sound such as adults employ when surprised. Thus Darwin reports.

My boy gave me occasion for the following observations:

In the eleventh week he does not see himself in the glass. If I knock on
the glass, he turns his head in the direction of the sound. His image
does not, however, make the slightest impression upon him.

In the fourteenth and fifteenth weeks he looks at his image with utter
indifference. His gaze is directed to the eyes in the image without any
expression of pleasure or displeasure.

In the sixteenth week the reflected image is still either ignored or
looked at without interest.

Near the beginning of the seventeenth week (on the one hundred and
thirteenth day) the child for the first time regards his image in the
glass with unmistakable attention, and indeed with the same expression
with which he is accustomed to fix his gaze on a strange face seen for
the first time. The impression appears to awaken neither displeasure nor
pleasure; the perception seems now for the first time to be distinct.
Three days later the child for the first time undoubtedly laughed at his
image.

When, in the twenty-fourth week, I held the child again before the
glass, he saw my image, became very attentive, and suddenly turned round
toward me, manifestly convincing himself that I stood near him.

In the twenty-fifth week he for the first time stretched out his hand
toward his own image. He therefore regarded it as capable of being
seized.

In the twenty-sixth week the child is delighted at seeing me in the
glass. He turns round toward me, and evidently _compares_ the original
with the ima