There is also to be noticed the "breaking" of the voice which occurs in man at the age of puberty, and is connected with the nervous system.
In women the body is smaller and more delicate, the bones weaker, the pelvis wider and the chest narrower. The normal woman has no beard while the pubic hairs are the same as in man. The pubis, covered with a layer of fat, is slightly prominent in women and is called the mons Veneris. There is more fat under the skin in a woman's body, and the voice does not break. After puberty breasts develop with their lactiferous glands and nipples for suction. Puberty takes place a little earlier in women than in men, and corresponds to the growth of the internal and external sexual organs, at the same time that the ovules commence to mature and menstruation is established.
The mental correlative sexual characters are much more important than those of the body. The psychology of man is different from that of woman. Many books have been written on this subject, usually with more sentimentality than exactitude. Mysogynists, like the philosopher Schopenhauer, disparage woman from all points of view, while the friends of the female sex often exalt her in an exaggerated manner. In contemporary literature we see women authors judging man in quite different ways according as they are affected with "misandery" or "philandery"—that is enemies or friends of men. Quite recently Moebius has published a mysogynistic work on the "Physiological Imbecility of Woman." (Der physiologische Schwachsinn des Weibes). One must be a misogynist of very high degree to introduce the pathological notion of imbecility into the evolution of the normal mentality of woman. In reality, the individual differences are much greater in man and woman from the psychological than from the physical point of view, so that they render a definition of the average extremely difficult.
We are acquainted with bearded women, athletic women, as well as beardless men and puny men. From the mental point of view, there are also viragos and men with feminine instincts. Imbeciles are not wanting in both sexes, but no reasonable person will deny that an intelligent woman is superior to a narrow-minded man even from the purely intellectual point of view. In spite of these difficulties, I shall attempt to bring forward the principal points which distinguish, in a general way, the masculine mind from the feminine, relying on my own observations and especially on the mental phenomena of both sexes.
The Weight of the Brain.—According to statistics, the weight of the brain in men of our race is on the average 1350 grammes, while that of women averages 1200 grammes. The absolute weight is, however, not of much importance, because part of the cerebral substance in the larger animals is only for the supply of a greater number of cellular elements of the rest of the body, which necessitates a greater number of nervous elements.
To make the matter clear, it is necessary to separate the weight of the cerebral hemispheres from the other nervous centers, such as the cerebellum, corpora striata, the optic thalami, the mid-brain, the pons Varolii, the medulla oblongata and the spinal cord, for these centers constitute parts which are phylogenetically older, that is to say, inherited from lower animal ancestors. Compared with the cerebral hemispheres, these nerve centers are relatively more important in other vertebrates than in man, and are in more constant proportion to the size of the body, the muscular, glandular and sensory elements of which they supply. When the intelligence is about the same, they are, therefore, compared with the cerebral hemispheres, much more developed in the larger than in the smaller animals. For example, they are very large in the ox, but small in mice. I have weighed a considerable number of human brains separated in this way with the following results:
| CEREBRAL HEMISPHERES | OTHER CEREBRAL CENTERS |
| Man 1060 grammes, 78.5% | 290 grammes, 21.5% |
| Woman 955 grammes, 77.9% | 270 grammes, 22.1% |
Thus the cerebellum and basal ganglia are a little smaller in men than in women, compared with the cerebral hemispheres.
These figures appear to show that the cerebral hemispheres in woman are on the average a little smaller than in man, even proportionately to the stature; for, according to a general law in the animal kingdom, woman being smaller, her cerebral hemispheres should be, with equal mentality, proportionately a little larger. There are, however, female brains larger than many male brains, and the absolute and relative size of the cerebral hemispheres does not give a complete measure of the productive faculties. Remarkable men have been known to possess rather small brains and imbeciles heavy ones. We must not forget the great importance of the hereditary or engraphic predispositions of the nerve element or neurone, to certain activities and especially to work in general, that is to say, their aptitude to produce energy, or if one prefers it, their disposition to "will."
It is also interesting to consider the relationship of the frontal lobe to the rest of the cerebral hemispheres, the frontal lobe being without doubt the principal seat of intellectual activity. According to Meynert, the weight of the frontal lobe in man exceeds that of woman, not only absolutely, but relatively to the rest of the brain. In his résumé of the statistical data collected on this subject and from the results of my own material (autopsies at the asylum of Burgholzli in Zurich), Mercier has confirmed the opinion of Meynert. The average weight of the hemispheres separated from the rest of the brain is 1019 grammes in man (frontal lobe 428, the rest 591), and 930 in woman (frontal lobe 384, rest 546). Here, atrophied brains (except general paralytics) have been weighed with others, which lowers the average total weight without altering the proportion. Thus, the rest of the cerebral hemispheres exceeds the frontal lobe by 163 grammes in man and 162 grammes in woman, which means that in man the frontal lobe constitutes 42 per cent. of the cerebral hemispheres and in woman 41.3 per cent. The difference is not great, but it is definite, for it is based on a large number of observations.