VARIATION IN MAN AND WOMAN. 247 



valuable it may be in other respects, has no decisive bearing on the 

 question he undertook to answer, and can have no very damaging 

 effect on the writers he attacks. But there is considerable interest 

 in driving the point of the discussion still further home. 



It may be agreed that since differences in size are probably affected 

 by the influences of life and death to a considerable extent, and per- 

 haps unequally eliminated in the two sexes, they do not form a 

 reliable guide to the sexual incidence of variations. But, it may 

 be argued, this cannot affect measurements made at birth, and we 

 must therefore accept the validity of those of Professor Pearson's 

 measurements which concern the infant at birth. Here, however, we 

 encounter a fact which is of the first importance in its bearing on 

 our subject: the elimination of variations in size has already begun 

 at birth, and there is reason to suppose that that elimination unequally 

 affects males and females. This was duly allowed for in 'Man and 

 Woman,' but there is no hint of it throughout Professor Pearson's 

 long paper. He does not dispute this influence, nor does he realize 

 that until he has disputed it his conclusions can not be brought to 

 bear against mine. Professor Pearson's earlier statistical excursions 

 into the biological field were chiefly concerned with crabs; in passing 

 from crabs to human beings he failed to allow for the fact that 

 human beings do not come into the world under the same conditions. 

 I make no large claim for superior insight in this matter; it was 

 probably a question of training; I was practically familiar with the 

 phenomena of childbirth; he was not. But his ignorance has pro- 

 foundly affected the validity of his cherished criterion of sex vari- 

 ability, in so far as it is used against his predecessors in this field. 



Every child who is born into the world undergoes a severe ordeal, 

 due largely to the limited elasticity of the bony pelvic ring through 

 which it has to pass. Probably as a result of this, a certain propor- 

 tion perish as they enter the world or very shortly after. Among 

 the number thus eliminated there appears to be a very considerable 

 proportion of the largest infants. Doubtless because male infants 

 tend to be larger than female infants, males suffer most at and shortly 

 after birth. This appears to be the rule everywhere.* 



So far as I am aware, the first attempt to explain this matter 

 scientifically was made in 1786 by an English doctor named Clarke, 

 physician to the Lying-in Hospital at Dublin. f By weighing and 



* For the exact proportion of male to female still-born children in most 

 civilized countries, see, e. g., Ploss, ' Das Weib,' 7th edition, 1901, Vol. I., p. 336. 



f Joseph Clarke, ' Observations on some Causes of the Excess of the 

 Mortality of Males above that of Females,' Philosophical Transactions, 1786. 

 It may be said here that the very first attempt to weigh and measure infants 

 accurately had only been made not so many years previously, by Roederer, in 

 1753. 



