Thomas Dwiglit 35 



Even the last is far from a bad result and shows that the size of 

 the head of the femur has a great sexual significance, but distinctly less 

 than that of the head of the humerus. The averages show the same 

 thing, though less strikingly. 



The main thesis seems thus to be established. 



Let us now consider whether any particular shape of the articular 

 head is more characteristic of either sex than another. As we have 

 begun by assuming that the head of the femur is spherical, there can be 

 no question about that; but as the head of the humerus has a long and 

 a short diameter the question is possible. From some old observations on 

 the glenoid cavity I had come to the conclusion that the head of the 

 female bone is narrower than that of the male, and this is supported by 

 the averages; but to such a minute degree as to be unworthy of con- 

 sideration. As already stated, the female head of the humerus meas- 

 ures 87.51 per cent of the male in the vertical direction, and 87.28 in 

 the transverse. The average difference in the former direction is 6.09 

 mm., and in the latter 5.68 mm. The transverse diameter is 91.59 per 

 cent of the vertical in the male, and 91.35 per cent in the female. I then 

 went to work on the individual differences between the vertical and the 

 transverse diameters. The range of differences extends from — 1 to 8 

 mm. The former means that in one single female bone the transverse 

 diameter was 1 mm. greater than the vertical. No difference whatever 

 was found in 3 males and 2 females. The difference was 1 mm. in 10 

 males and 13 females; the greatest difference, 8 mm., was found in 2 

 of each sex. Differences of 6 and 7 mm. were found much more fre- 

 quently among the males than the females, as is to be expected from 

 the greater size of the former. Kunning through a number of cases in 

 both sexes in which the difference was slight and of others in which 

 it was large, I was quite unable to see anything that pointed to a sexual 

 difference in this respect sufficiently marked to be worth recording. 

 J was unequally unsuccessful in trying to ascertain whether, regardless 

 of sex, a long or a round head of the humerus was to be expected more 

 frequently in large or small bones. 



I endeavored to ascertain whether the difference betw-een the head of 

 the humerus and that of the femur was greater in one sex (probably 

 the female) than the other, but I failed again. The average differ- 

 ence of the vertical diameters show^ed a difference to the advantage of 

 the femur of .92 mm. for the male, and 1.17 mm. for the female. 

 On the other hand, the transverse diameter gave the femur an advan- 

 tage of 5.02 mm. in tlie male, and 4.SG in the female. Study of indi- 



