D.— ZOOLOGY 97 



tion by death ; amongst those aged 75 and over actually more females 

 than males die for the very simple and obvious reason that amongst the in- 

 dividuals of 75 and over awaiting death there are far more females than males. 



It would appear from these figures alone that to be born is a more 

 dangerous adventure for the male than for the female, and that there is 

 a sexually selective mortality which not only operates at all ages after 

 birth to the disadvantage of the male, but which acts and possibly 

 equally strongly pre-natally as well. The expectation of life at all ages 

 is greater in the case of the female of the species, and the true recipe for 

 longevity is to be born a girl. The political power of women in a demo- 

 cracy such as ours, which pretends to disregard sex diflFerences, is much 

 less than that which their numbers could command. 



A considerable number of other facts and observations concerning the 

 human sex ratio and relevant to the present discussion are easily found 

 in the abundant literature that deals with this particular subject. It is 

 generally accepted, for example, that the sex ratio amongst abortuses is 

 higher than that amongst still-births, and there is sufficient reason for 

 holding the view that the sex ratio amongst abortuses of the earlier months 

 of intra-uterine life is much higher than that amongst those of the later 

 months. It has been shown that the secondary sex ratio is influenced 

 by urbanisation, being lower in county boroughs than in rural areas. The 

 secondary sex ratio would seem to be affected by' social upheavals. It is 

 commonly held, for example, that in those countries directly engaged in the 

 Great War the secondary sex ratio was high immediately following the 

 cessation of hostilities and higher immediately after than immediately 

 before the War ; neutral countries affected commercially by the War 

 experiencing the same phenomenon, though not to the same extent. The 

 secondary sex ratio is highest amongst the first-born, and declines with 

 increasing size of family in a curvilinear manner. It is influenced by 

 migration, the migrants having a higher or a lower secondary sex ratio 

 than their relatives who remain in the homelands. Usually it is lower 

 amongst illegitimates than amongst living children born in wedlock. 

 As a rule it is lower amongst coloured people than amongst the whites 

 amid whom they live. It is affected by social status, being higher in the 

 upper and middle classes and lower amongst the unskilled workers. In 

 places and in periods where infant mortality is high the ratio of boy deaths 

 to girl deaths is low, and where there is a low rate of infant mortality the 

 death rate of boys is relatively high. With the reduction of infant 

 mortality that has occurred within recent years there has been a marked 

 relative increase of boy deaths. The sex ratio at death amongst infants 

 during the first year of life varies with the age of the infants : for the very 

 young it is high, but decreases during the year. 



A consideration of these facts must ultimately lead to the conclusion 

 that in the case of man, for some reason or other, the male, in virtue of 

 his maleness, is less viable than the female, so that, under unfavourable 

 circumstances, both pre-natally and post-natally, the male, because of 

 this greater inherent fragility, suffers more easily and more severely than 

 does the female, and is removed from the population by death in greater 

 numbers. Furthermore, since this selective elimination of the male occurs 



