than this, the
boys become equal to the girls, and still later surpass them. Very
striking is the fact, one upon which a very large number of
investigators are agreed, that girls have a superior knowledge of
colours. Experimental investigations made by means of Holmgren's test
have shown that the superiority of girls in this respect is remarkable,
and these experiments are confirmed by other lines of study.

There are additional psychological data relating to the differences
between the sexes in childhood. I may recall Stern's investigations
concerning the psychology of evidence, which showed that girls were much
more inaccurate than boys. I may also refer, on the other hand, in
relation to sexual differentiation, to the experiences obtained by Hans
Gross by means of observations on practical life, although his results
are not entirely free from certain sources of fallacy, and moreover have
been disputed by other observers as not generally applicable. Hans
Gross, however, found a notable difference between boys and girls, of
which I shall later give a detailed description. Here, I shall merely
quote the comprehensive summary given in his _Criminal Psychology_: "My
results show that the boy who has passed his first years of childhood
is, if well trained, the best observer and witness that can possibly be
found, because he watches with interest all that goes on around him,
stores it impartially in his memory, and reproduces it faithfully;
whereas the girl of like age is often an untrustworthy, and even a
dangerous witness. She is inevitably this when, after traversing the
stages of talent, ardour, reverie, romanticism, and enthusiasm, she has
passed into a condition of _Weltschmerz_, tinged with _tedium vitae_.
This emotional mental atmosphere is entered at an earlier age than is
commonly imagined; and when such a girl's own personal interests are in
any way affected by the occurrences under examination, we are never
secure from gross exaggeration and misstatement. Petty larceny becomes
robbery with violence; a trifling incivility, a serious assault; a
harmless pleasantry, an interesting proposal for elopement; and the
foolish prattle of children becomes a dangerous conspiracy."

I shall subsequently discuss in detail a psychical difference which is
the most important of all those connected with the sexual life, namely,
the direction of the sexual impulse, which attracts the man to the
woman, and the woman to the man. We