“The question immediately arises, whether we are justified in speaking of the mental ‘inferiority’ of woman, because her brain weighs less than that of man. “Now, in the first place, it is obvious that the greater body-weight of man demands a greater weight of brain. And there is nothing remarkable about the fact that the greater size exhibited by many organs of the male should be exhibited also by the brain. It seems very natural that the unquestionably greater functional activity which has distinguished the masculine brain for many thousand years should be manifested by the notably greater size of that organ, just as a larger muscle generally performs more work than a small one. “As a matter of fact, among the numerous investigators occupied with this question, many have assumed that differences in the psychical power of human brains are dependent upon differences in their size. But this is an =assumption= merely, and with Bischoff, who as long as forty years ago conducted an exhaustive investigation into the problem of the relations between brain-weight and intellectual capacity, we must say also to-day that ‘the proof of any such connexion has =not= yet been offered us.’” Whether the study of the finer structure of the brain in man and woman will enable us to form more trustworthy conclusions regarding their respective intellectual valuation, is a question whose answer must for the present be postponed. According to Rüdinger and Passet, in new-born boys and girls there exist very remarkable differences in the formation and development of the brain. In the male fœtal brain the frontal lobes are larger, wider, and higher; the convolutions, especially those of the parietal lobe, are better formed than in the female fœtal brain. Waldeyer was able to confirm this observation, and he considers it of great importance, especially in view of the large share which the frontal lobes have in the performance of purely intellectual functions. Broca, however, was unable to detect a lesser development of the frontal lobes in woman. Eberstaller and Cunningham even believed that they could establish that this portion of the brain was more powerfully developed in woman! Finally, the great Swedish cerebral anatomist, G. Retzius, made an exact investigation of the sexual differences between the brains of man and woman in the adult state. According to O. Schultze, his results can be regarded as authoritative. Retzius stated that =hitherto no specific invariably recurrent peculiarity had been found by which the female brain could always with certainty be distinguished from the male; still, he was inclined to attribute to woman’s brain a greater simplicity of structure; it showed less divergence from the fundamental type=.