In most cases, the complete association of the processes of detumescence and contrectation, such as occurs in the impulse towards coitus, first takes place at a somewhat later age. This is so even when the sensory element, which constitutes a part also of the contrectation impulse, has been already clearly manifested. The contrectation impulse does not consist solely in this, that the boy experiences a purely spiritual love for the girl; it may rather happen that certain definite sexual bodily peculiarities in a woman attract him. When such a boy one day unexpectedly sees a girl's breasts, this may exercise on him a powerful stimulus. Similarly, I have known instances in which, in the absence of any evidence of definite seduction, a woman's genital organs have excited a very young boy, without arousing any idea in his mind of contact between _his own_ genitals and those of the woman. Conversely, on many girls, masculine attributes, and especially the male genital organs, sometimes exert a stimulating influence. But in these cases also, the complete fusion of the processes of detumescence and contrectation occurs very gradually. Sometimes the boy himself is greatly astonished to discover that close contact with a person whom he loves leads to erection and even ejaculation. At the outset the impulse is much less definite than it is in adults. It is by gradual stages only that the sense of indefinite longing develops into the impulse towards sexual union in coitus; at first the imagination contemplates pictures of a quite indefinite character.