I feel it necessary to add that their importance in relation to our subject of study is comparatively trifling, since most of the cases in question are offences committed by persons who can no longer properly be regarded as children. As we have seen, during childhood, and especially during the second period of childhood, there exists a larger number of sexual differences both mental and physical. Some of these are obviously discernible when we compare isolated individuals; others only become apparent when we institute a statistical comparison. And when such differences appear in childhood, we find that they are quantitatively less extensive than the sexual differences of adults. For the sexual life is in the child less developed than it is in the adult. We shall learn that in the matter of the sexual impulse, the child exhibits an imperfect differentiation. A similarly imperfect differentiation is found in childhood in respect of a number of other qualities. Thus, there are many diseases which later in life manifest a sexual differentiation, but in childhood are undifferentiated. We observe a similar age-distinction in respect of suicide, which occurs in Europe far more frequently in men than in women, the ratio among suicides being three or four men to one woman. Among child-suicides there is far less disproportion between the sexes. According to Havelock Ellis, indeed, the suicidal tendency makes its appearance in girls at an earlier age than in boys. Such a marked differentiation as there is between the adult man and the adult woman certainly does not exist in childhood. Similarly in respect of many other qualities, alike bodily and mental, in respect of many inclinations and numerous activities, we find that in childhood sexual differentiation is less marked than it is in adult life. None the less, we have learned in this chapter, a number of sexual differences can be shown to exist even in childhood; and as regards many other differences, though they are not yet apparent, we are nevertheless compelled to assume that they already exist potentially in the organs of the child. CHAPTER IV SYMPTOMATOLOGY The data recorded in the preceding chapter suffice to show that the activity of the sexual life begins in childhood, for the secondary sexual characters and the other sexual peculiarities which manifest themselves thus early in life are dependent upon sex. We shall now proceed to the systematic description of the direct manifestations of the sexual life, and we can most usefully begin with the genital organs.