Heredity and eugenics in relation to insanity / by F.W. Mott.

  • Mott, F. W. (Frederick Walker), 1853-1926.
Date:
[1912]
Catalogue details

Licence: In copyright

Credit: Heredity and eugenics in relation to insanity / by F.W. Mott. Source: Wellcome Collection.

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    menstrual periods, child-bearing, and the cessation of the period of repro¬ duction, the climacterium. I would also add as an important and perhaps the only cause in many instances the enforced suppression by modern social conditions of the repro¬ ductive functions and the maternal instincts in women of an emotional temperament and mental instability. Anticipation or Antedating. Dr. Maudsley has observed that Nature tends to mend or end a de¬ generate stock. Now, how could Nature best end or mend a degenerate stock ? Obviously by segregating in a relatively few germs all the unsound elements, leaving the others as it were free. The accompanying figure 15 helps to explain this theory. Assuming the intensity of inheritance is constant for each chromosome or other unit of germ-plasm, but to vary with the number of the germinal units tainted, we have as a result of the mating of these two tainted stocks all degrees of manifestation of ancestral characters from perfect normality to the most profound disease. The more numerous the tainted germinal units the greater will be the chance of the disease appearing in the offspring. On the other hand, the oftener reduction, with its possible random arrange¬ ment, has occurred—i.e., the greater the number of generations—the less will be the chance of any particular character finding a place in the inheri¬ tance (Nettleship). A. fartnt Ch»om©som<5 8 reduced to 4.15 6 116 7 t*X7E 3«,S& 3467 3478 m® m® ©® @0 @0 4• A.& A4 4A AA kk AA o- b c Cl el. Mfctnl. { >ii-v S 6 7 s V AAAA B. 4 it n 1* ir 14 . ( 0000 bcxo ] I ‘5. *tO H is ©O ©0 £□ DO 9 h A. Somt result* of. ^ X 8 ^ ^ Chromosomes d xh » VHfVlIlDOWlllVI .lift 9 10 15 , 3 ( J 6 s # n If . [ G0ga j 8 [ <j)C>A4 0BDD ] | to | 4 io tL.S9.t0 rA.9.10 S-6.l3.tf 3-4-1 ■» 4.j:» 5^ 4.1.14.1s 3.6 $.14 ®A A4 A.& 4 rnO OA OA OA #4 ©E7 ©0 ©0 EQ T ©0 ©0 ©Q G7Q Fig. IS A—represents the male parent ; his immature germ-cells have derived their chromosomes, germinal determinants or representative particles (Galton) from his father and mother, and they are respectively represented bj different figures. The eight germ-mature chromosomes are reduced to four during maturation, two from each parent; the figures a-f indicate the combination of two maternal with two paternal, all diseased, but in different degrees and modes. B—represents the female parent, in which there is an inherited taint, but only to a slight degree, coming from the maternal side ; in the mature germ-cells only one containing number 13 will be tainted. C—shows some of the results which may arise from the conjugation of A X B. Certainly this idea of the scheme explains certain facts which have been observed in the pedigrees I have shown; it shows why the offspring of