According to the opinion of eminent authorities, the most marked differences in physical and mental qualities between man and woman are the following: In regard to stature, Havelock Ellis considers 170 centimeters the average height for men and 160 centimeters for women. According to Vierordt, it is 172 and 160, and in northern Germany, according to Krause, 173 and 163 centimeters. The proportion of man’s stature to woman’s is as 100 to 93. The average weight of adult persons is 65 kilograms for men and 54 for women. The greater length of the trunk in a woman’s body is a well-known difference; yet this difference is not as great as has been generally assumed, as careful measurements have shown. The legs of a woman of medium size are only by 15 millimeters shorter than those of a man of medium size, and Pfitzner doubts that this difference is noticeable. “The differences in the lengths of body and legs are influenced by the stature, and are independent of sex.” But the female arm is decidedly shorter than the male arm (as 100 to 91.5). The male hand is broader and larger than the female hand, and with men the ring-finger is usually longer than the index, while the opposite is the case with women. By this the male hand becomes more ape-like, as the long arm also is a pithecoid (ape-like) characteristic. In regard to the size of the head, the proportion of the absolute height of male and female heads may be set down as 100 to 94. But the relative sizes (in proportion to the size of the body) are 100 to 100.8. So actually woman’s head is somewhat smaller, but in proportion to the size of her body, it is somewhat larger than man’s. The bones of woman are smaller, finer, and more delicate in form and have a smoother surface, for the weaker muscles require less rough surface to fasten upon. The weaker muscular development is one of the most striking characteristics of woman. Each separate muscle of a woman’s body is finer, softer, and contains more water. (According to v. Bibra the quantity of water contained in the muscles is 72.5 per cent. with man, and 74.4 per cent. with woman.) In regard to the adipose membrane the opposite proportion exists; it is much more amply developed with woman than with man. The chest is relatively shorter and narrower. Other differences are directly connected with the sexual purpose. The statements of various authors in regard to relative and absolute weight of the intestines, are very contradictory. According to Vierordt the proportion of the weight of the heart to the weight of the body is as 1 to 215 with men, and as 1 to 206 with women. According to Clendinning it is as 1 to 158 and as 1 to 149. Taken all in all, we may assume that the female intestines are absolutely smaller, but relatively, in proportion to the weight of the body, heavier than the male.