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One of each pair goes into one daughter-cell and the other into the other, but not all maternal into one and all paternal into the other. Thus each daughter-cell after the first or heterotypic division in normal cases contains 7 chromosomes. A second homotypic division takes place in which each chromosome splits into two as in somatic divisions, and thus we have 4 gametes with 7 chromosomes each.
Such a conclusion inevitably suggests that the investigator is proving too much. The subject of the influence of hormones from the gonads is mentioned, but not fully discussed, in a volume by Dr. Origin Of Somatic Sex-Characters In Evolution
It is evident from the conditions in these mammals that both hair and milk glands were evolved before the placenta. It may also be pointed out here that, according to the evidence of Steinach, in the milk glands at least among somatic sexual characters there is no difference between the male and female in the heredity of the organs.
It is well known how Weismann was led, by his hypothesis of the continuity of the germ-plasm, to regard the germinal cells ova and spermatozoa as almost independent of the somatic cells. Starting from this, it has been claimed, and is still claimed by many, that the hereditary transmission of an acquired character is inconceivable.
Of course, a lesion somewhere outside the brain is not unlikely to be projected through the diseased brain, and SOMATIC delusions in the paretic are rather likely to represent something in the viscera. It was desirable to get back to normal-brain material, to learn how the INTRINSICALLY NORMAL brain could perhaps produce delusions from a particular environment.
The fact that castration does affect, in many cases very profoundly, somatic characters confined to one sex, proves that Mendelian conceptions, however true up to a certain point, are by no means the whole truth about heredity and development. For it is the essence of Mendelism as of Weismannism that not only sex but all other congenital characters are determined in the fertilised ovum or zygote.
Long ago, Hippocrates, revered founder of the art of medicine, recognized that there was a specific affinity of disease for individuals with more or less the same characteristic somatic and psychic traits and trends. Tuberculosis, for instance, was noted for its frequency in long-skeletoned, thin persons, remarkably optimistic.
Patriotism is aroused, for thus the country can be better served; thus the German Fatherland was to be restored and unified after the dark days that followed the humiliation of Jena. Now the ideals of religion are invoked that the soul may have a better and regenerated somatic organism with which to serve Jesus and the Church.
But the very constitution of the germ-plasm and its relation to the body absolutely forbids the transmission of acquired somatic characteristics and of the special effects of use and disuse. Muscular activity promotes general health, and might thus conduce to better-nourished germ-cells and to more vigorous and therefore athletic descendants.
The material summarized in the preceding paragraphs furnish some slight inkling of the vast dominion of Sex, in all its relations, somatic and spiritual, over which the glands of internal secretions rule. The founder of modern pathology, Virchow, said that woman is woman because of her ovaries.
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