German clinicians have recently pointed out that the existence of an excess of pressure on the frontal lobes of the brain, such as is produced by the presence of a tumour, may cause a tendency to make little jokes. This symptom is known as "Witzelsucht." It is considered of distinct significance and value in localising tumours of the brain. The question of the type of the witticisms and particularly a tendency to obscenity are noted as a special diagnostic aid in the recognition of the character of these tumours by at least three prominent German medical observers. If modifications of the brain substance can produce changes of disposition and temperament, it is easy to understand how temperament and disposition may be a matter of inheritance. If we inherit a father's nose and a mother's eyes, {225} the minutest conformations of brain substance may also be inherited. It is on these, to a certain extent at least, that the general outlines of the disposition depend. It would not be surprising to find, then, a disposition to mental unsteadiness as the result of the transmission of brain peculiarities. Here, as in everything else, there is question, not merely of parental influence, but of the inheritance of the family traits, some of which are skipped in certain generations. When melancholia and mania are said to be due to heredity as one of the principal causes, the meaning intended is that in certain families the brain tissues are liable to be transmitted in somewhat impaired condition, and that through these brain tissues the mind will either not act properly, or under the stress of violent emotion, the loss of friends by death, or the loss of fortune, or serious disappointments in life, or a love affair, the already tottering mental condition will be overturned. In a word, it is not the direct transmission of insanity, but of a predisposition to the development of insanity under stresses and strains that is a matter of family inheritance. This is considered true now not only of mental but of all diseases. Not consumption, but the predisposition to it is inherited. These considerations make clear how important this matter of heredity is. Physicians and students of anthropology are so much concerned about the increase of insanity as the result of the intermarriage of defectives that we are constantly reading in the newspapers of attempts at the legal regulations of marriage, so as to prevent further racial degeneration. Under present circumstances, any such legal regulation is probably impossible; but it seems perfectly clear that clerical influence should be brought to bear to discourage, as far as possible, intermarriage among those of even slightly disturbed mental heredity. Especially must any such idea as the possible beneficial influence of matrimony (for there are popular traditions to this effect) be unhesitatingly rejected and it must not be allowed to tempt those interested to look on such intermarriage with indifference. {226}