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Updated: April 30, 2025
A vitality is created which makes him bound and dart like a youth of his species. In due time, though, senility returns. It is as if a storage battery, recharged, runs down and becomes dead again. Slitting the genital duct of the other testis, causing its interstitial cells to hypertrophy and multiply, repeats the effects of the first experiment.
Ovary and adrenal medulla and posterior pituitary and thyroid predominance constitute the feminine formula. Testis and adrenal cortex and anterior pituitary predominance comprise the masculine endocrine directorate. As in so many other aspects, the facts about the various influences exerted by the endocrine glands upon the reproductive system are complicated and disjointed.
It seems impossible that the horny layer or its papillae could atrophy in consequence of castration, or be absorbed. Meisenheimer claims that he produced development of papillae on the thumb-pad, not only by implantation of pieces of testis, but also by implantation of pieces of ovary.
It would seem that the development of this character is dependent on the hormone from the mature testis, and in order to conform with the arguments used by me in other cases, the spinulation should have some definite function in relation to the habits of the sexes, and this function should involve some kind of external stimulation restricted to the mature male.
This seems so very improbable that it suggests a doubt whether the same investigator was not mistaken with regard to the results of his experiments in transplanting gonads in Moths. Smith and Schuster conclude that the normal development of the thumb-pad depends on the presence of normal testes, but that there is no sufficient evidence that the effect is due to a hormone derived from the testis.
'It can hardly be maintained that this is an example of assumption by the male of the female's plumage, especially as the presence of the testis is necessary for its appearance. The idea here seems to be that since the eclipse plumage is only assumed when the testis is present, therefore it must be a male character.
The factors in these chromosomes corresponding to the forehead have been stimulated while in the parent animal by hormones from the outgrowth of tissue produced by external mechanical stimulation, while at the same time they were permeated by the testicular hormone produced either by the gametocytes themselves or by interstitial cells of the testis.
This lengthened scrotum with its contents may also be exposed to mechanical pressure or even to injury from the clothing, etc., which would not occur if the scrotal sac were short, holding the testes close to the body. Of far more importance is the danger of the varicocele gradually encroaching by pressure upon the testis, perhaps to cause a partial atrophy of that gland.
By sex here he obviously means the instincts and somatic characters, for sex in the first instance, as we have already pointed out, means the difference between ovary and testis, between ova and spermatozoa. It is difficult to accept all Steinach's results without confirmation, especially those which show that the feminised male is more female than the normal female.
According to my theory there are two hormone actions, the centripetal from the hypertrophied tissue to the corresponding factor in the gametocytes, and the centrifugal from the testis to the tissue of the antler or other organ concerned.
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