On the other hand, it is quite normal for young girls and boys to show early signs of mental differences corresponding to those we have described in Chapter V. In young girls we observe coquetry and jealousy and the desire for finery. Their love of dolls and the care they take of them, is very characteristic of the precocious instinct of their sex. This is an early sign of instinctive maternal love, before the development of any sexual sensation or function. Among boys we observe a tendency to brag and to boast of their strength before girls, to show their contempt for dolls and the coquetry of little girls, and also to pose as protectors, etc. Sexual jealousy already exists in young children. We see little boys, seeking for the favors of little girls, show violent jealousy when another is preferred to them. All these phenomena depend either on subconscious instincts, or on vague sexual presentiments which play a large part in the infantile exaltation of sentiment. Portraits of pretty women, the sight of certain parts of the body or feminine clothing often provoke exalted sentiments in boys; girls rather admire boldness, an imposing presence and often beauty, in the other sex. Puberty is produced by certain phenomena which occur in the sexual organs. In the boy erections occur at an early age when the penis is still very small. It is curious to note that certain pathological conditions and friction of the glans penis, especially in the case of phimosis and as a result of bad example, are often sufficient to produce sexual sensations and appetites in very young boys. The same thing is produced in little girls by excitation of the clitoris. All these phenomena lead to onanism or masturbation, of which we shall speak later on. As the testicles of young boys do not secrete semen, masturbation only provokes secretion from the accessory glands, but this is accompanied by orgasm. More singular still are cases of coitus between little boys and girls whose sexual glands are still undeveloped and produce no germinal cells. Although they are pathological, these phenomena are characteristic, because they clearly show that the brain has acquired by phylogeny a sexual appetite relatively independent of the development of the sexual glands. No doubt the sexual appetite does not develop, or disappears, in eunuchs when they are castrated quite young; but it is preserved together with the secretions and functions of the external genitals when castration is performed after puberty is established. The important conclusion which results from these facts is that the existence of a sexual excitation or appetite of this nature is not sufficient to prove that they are normal. In Chapter VIII we shall prove that not only the anomalies of the hereditary sexual disposition, but artificial excitations and bad habits may also produce all kinds of misconduct and excesses which should be energetically combated.