All these facts, almost inexplicable hitherto, become comprehensible by the aid of the engraphia of the mnemic energies. (Vide above; _Semon_). The sexual glands, being of undifferentiated origin, contain the energies of both sexes. The ecphoria of one of them provokes that of its correlative characters and excludes that of the characters of the other. If ecphoria of the sexual glands is arrested by castration before it is finished, this paralyzes the predominance of that of its corresponding correlative characters and reëstablishes a kind of intermediate or undifferentiated equilibrium between the ecphorias of the correlative hereditary sexual characters of the two sexes. On the other hand, if the sexual glands of an adult are removed, his body is not sensibly modified. The sexual functions do not cease completely, although they cannot lead to fecundation. Men castrated in adult age may cohabit with their wives; but the liquid ejaculated is not semen but only secretion from the accessory prostatic gland. Adult women after castration preserve their sexual appetite, and sometimes even their menstruation, for a certain time. They generally become fat and often suffer from nervous troubles and change in character. The ecphoria of the correlative sexual characters being complete in the adult, suppression of the sexual glands can only act on their direct functions. In different species of animals, the correlative sexual characters of which we have spoken vary enormously; sometimes the differences are insignificant, at other times they are considerable; while we can hardly distinguish a male swallow from a female, the cock and hen, the peacock and peahen, the stag and hind are very different from each other. In man, the correlative sexual characters are very distinct, even externally. These characters may extend to all parts of the body, even to the brain and mental faculties.