Castration. Correlative sexual characters.—Castration is the term applied to the extirpation of the sexual glands. When it takes place in infancy it causes a considerable change in the whole subsequent development of the body, especially in man, but also in woman. Man becomes more slender, preserves a high and infantile voice, and his sexual correlative characters develop incompletely or not at all. Eunuchs are men castrated, usually in infancy. To ensure more safety in their harems the Orientals not only remove the testicles but also the penis. Bullocks and horses are bulls and stallions castrated at an early age, and can be distinguished at first sight from normal males. Females who have undergone castration become fat and sometimes take on certain masculine characters. Male human eunuchs have a high-pitched voice, a narrow chest; they remain beardless or nearly so, and have an effeminate character, often intriguing. In both sexes there is a tendency to neurosis and degeneration. It is a mistake to qualify the peculiarities of the male eunuch in the terms of female peculiarities; there is only a relative tendency. The eunuch is no more a woman than a bullock is a cow.
The characters of castrated individuals are due only to ablation of the sexual glands themselves—the testicles in man and the ovary in woman; mutilation of other sexual organs, internal or external, such as the penis, womb, etc., produces no result of this kind. It would even appear to result from recent experiments that reimplantation of a sexual gland in any part of the body is sufficient to arrest the production of the special peculiarities of the eunuch.
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.
In some of the lower animals, for example the ants, the sexes differ remarkably from each other and appear to belong to different zoölogical families. The eyes, the form of the head, the color, and the whole body differ so much that, when a case of pathological lateral hermaphrodism is produced (that is, when the sexual glands are male on the one side and female on the other), we can exactly determine the male or female character on each portion of the body. We thus see hermaphrodite ants with one half of the body male and the other half female—black on one side and red on the other, a large eye on one side and a small eye on the other, thirteen joints in one antenna and twelve in the other, and so on. In this case the mental faculties are sometimes female, sometimes male, according as the ecphoria of the brain is influenced by the hereditary mneme of the male or female part of the hermaphrodite sexual organs, which results in a male or female brain. I have seen hermaphrodite ants in which two parts of the thorax formed a crossed hermaphrodism; in front, male on the right and female on the left, behind female on the right and male on the left. Further; among ants which live in societies, the progressive transformation of the species, or phylogeny, has produced a third sex derived from the female sex—the worker; sometimes there is even a fourth—the warrior. In these two forms the wings are absent, but the head and brain are much larger; the sexual organs remain female, but are very small. While the large brain (pedunculated bodies of the supra-esophageal ganglion) is almost rudimentary in the male, it is well developed in the female and very large in the worker and the warrior. Among these singular animals exist pathological hermaphrodites, not only between males and females, but between males and workers, and not only lateral but mixed and crossed in all possible ways. I have seen a hermaphrodite, whose abdomen and sexual organs were almost entirely male, accomplish all the complex instinctive actions of a worker of his species (expeditions, attacks on a hostile ant heap, abduction of chrysalids), thanks to its head and brain which were of the worker type. The female itself is incapable of such complex actions. I cite these facts here as material for study, for we are only too prone in this domain to generalize prematurely and to draw too hasty conclusions. In reality, there is still a wide field for study of the greatest interest.
There are animals which are normally and physiologically hermaphrodite, for they possess in the normal state male and female sexual glands and fecundate themselves, such as the solitary worms, or in pairs such as the snails. In the latter case there is copulation, during which each animal plays the parts of both male and female.
In man and other vertebrates, hermaphrodism is always abnormal. In man it is extremely rare and nearly always very incomplete, being usually limited to the external or correlative characters.
Heredity.—It results from what we have said that every living being reproduces, more or less identically, in its specific characters, the whole life of its parents and less remote ancestors, and constitutes the continuation of life from a minute part of their bodies.
Each individual life thus repeats an entire cycle of development called ontogeny, which is peculiar to all individuals of the species. Here we must mention three fundamental points: