[1] So also in the opposite case; it cannot be wholly denied that ovariotomy is followed by the appearance of masculine characters.
The possession by every cell of primitive sexuality on which the secretion of the sexual glands has little effect might be shown further by consideration of the effects of grafting male genital glands on female organisms. For such an experiment to be accurate it would be necessary that the animal from which the testis was to be transplanted should be as near akin as possible to the female on which the testis was to be grafted, as, for instance, in the case of a brother and sister; the idioplasm of the two should be as alike as possible. In this experiment much would depend on limiting the conditions of the experiment as much as possible so that the results would not be confused by conflicting factors. Experiments made in Vienna have shown that when an exchange of the ovaries has been made between unrelated female animals (chosen at random) the atrophy of the ovaries follows, but that there is no failure of the secondary sexual characters (e.g., degeneration of the mammæ). Moreover, when the genital glands of an animal are removed from their natural position and grafted in a new position in the same animal (so that it still retains its own tissues) the full development of the secondary sexual characters goes on precisely as if there had been no interference, at least in cases where the operation is successful. The failure of the transplantation of ovaries from one animal to another may be due to the absence of family relationship between the tissues; the influence of the idioplasm probably is of primary importance.
These experiments closely resemble those made in the transfusion of alien blood. It is a practical rule with surgeons that when a dangerous loss of blood has to be made good, the blood required for transfusion must be obtained from an individual not only of the same species and family, but also of the same sex as that of the patient. The parallel between transfusion and transplantation is at once evident. If I am correct in my views, when surgeons seek to transfuse blood, instead of being content with injections of normal salt solution they must take the blood not merely from one of the same species, family and sex, but of a similar degree of masculinity or femininity.
Experiments on transfusion not only lend support to my belief in the existence of sex characters in the blood corpuscles, but they furnish additional explanations of the failure of experiments in grafting ovaries or testis on individuals of the opposite sex. The internal secretions of the genital glands are operative only in their appropriate environment of arrhenoplasm or thelyplasm.
In this connection, I may say a word as to the curative value of organotherapy. Although, as I have shown to be the case, the transplantation of freshly extirpated genital glands into subjects of the opposite sex has no effect, it does not follow that the injection of the ovarian secretion into the blood of a male might not have a most injurious effect. On the other hand, the principle of organotherapy has been opposed on the ground that organic preparations procured from non-allied species could not possibly be expected to yield good results. It is more than likely that the medical exponents of organotherapy have lost many valuable discoveries in healing because of their neglect of the biological theory of idioplasm.
The theory of an idioplasm, the presence of which gives the specific race characters to those tissues and cells which have lost the reproductive faculty, is by no means generally accepted. But at the least all must admit that the race characters are collected in the genital glands, and that if experiments with extracts from these are to provide more than a good tonic, the nearest possible relationship between the animals experimented upon must be observed. Parallel experiments might be made as to the effect of transplantation of the genital glands and injections of their extracts on two castrated cocks of the same strain. For instance, the effects of the transplantation of the testes of one of them into any other part of its own body or peritoneal cavity or into any similar part of the other cock might be compared with the effects of intravenous injection of testis extract of the one on the other. Such parallel investigations would also increase our knowledge as to the most suitable media and quantities of the extracts. It is also to be desired, from the theoretical point of view, that knowledge may be gained as to whether the internal secretion of the genital glands enters into chemical union with the protoplasm of the cells or whether it acts as a physiological stimulus independent of the quantity supplied. So far we know nothing that would enable us to come to a definite opinion on this point.
The limited influence of the internal secretions of the sexual glands in forming the sexual characters must be realised to warrant the theory of a primary, generally slight, difference in each cell, but still determinate sexual influence.[2] If the existence of distinct graduations of these primary characteristics in all the cells and tissues can be recognised, there follow many important and far-reaching conclusions. The individual egg-cells and spermatozoa may be found to possess different degrees of maleness and femaleness, not only in different individuals, but in the ovaries and testes of the same individual, especially at different times; for instance, the spermatozoa differ in size and activity. We are still quite ignorant on these matters, as no one has worked on the requisite lines.
[2] The existence of sexual distinctions before puberty shows that the power of the internal secretions of the sexual glands does not account for everything.
It is extremely interesting to recall in this connection that many times different investigators have observed in the testes of amphibia not only the different stages in the development of spermatozoa, but mature eggs. This interpretation of the observations was at first disputed, and it was suggested that the presence of unusually large cells in the tubes of the testes had given rise to the error, but the matter has now been fully confirmed. Moreover, in these Amphibia, sexually intermediate conditions are very common, and this should lead us to be careful in making statements as to the uniform presence of arrhenoplasm or thelyplasm in a body. The methods of assigning sex to a new-born infant seem most unsatisfactory in the light of these facts. If the child is observed to possess a male organ, even although there may be complete epi- or hypo-spadism, or a double failure of descent of the testes, it is at once described as a boy and is henceforth treated as one, although in other parts of the body, for instance in the brain, the sexual determinant may be much nearer thelyplasm than arrhenoplasm. The sooner a more exact method of sex discrimination is insisted upon the better.
As a result of these long inductions and deductions we may rest assured that all the cells possess a definite primary sexual determinant which must not be assumed to be alike or nearly alike throughout the same body. Every cell, every cell-complex, and every organ have their distinctive indices on the scale between thelyplasm and arrhenoplasm. For the exact definition of the sex, an estimation of the indices over the whole body would be necessary. I should be content to bear the blame of all the theoretical and practical errors in this book did I believe myself to have made the working out of a single case possible.
Differences in the primary sexual determinants, together with the varying internal secretions (which differ in quantity and quality in different individuals) produce the phenomena of sexually intermediate forms. Arrhenoplasm and thelyplasm, in their countless modifications, are the microscopic agencies which, in co-operation with the internal secretions, give rise to the macroscopic differences cited in the last chapter.
If the correctness of the conclusions so far stated may be assumed, the necessity is at once evident for a whole series of anatomical, physiological, histological and histo-chemical investigations into those differences between male and female types, in the structure and function of the individual organs by which the dowers of arrhenoplasm and thelyplasm express themselves in the tissues. The knowledge we possess at the present time on these matters comes from the study of averages, but averages fail to satisfy the modern statistician, and their scientific value is very small. Investigations into the sex-differences in the weight of the brain, for instance, have so far proved very little, probably because no care was taken to choose typical conditions, the assignment of sex being dependent on baptismal certificates or on superficial glances at the outward appearance. As if every “John” or