528 THE ROYAL SOCIETY OF CANADA 



(Part 3): "Among the factors of sex quilibrium the first to be 

 considered is the ratio of male and female births. Investigations 

 into the number of persons born into the two sexes date from the 

 beginning of statistics relating to population. Even in the 18th 

 century Suessmilch drew attention to the fact that there is a constant 

 relative excess in the number of boys; and Wappaeus (1812-1879) 

 found by a study of fifty-eight and a quarter million births in the larger 

 states of Europe that, for every 100 girls, the number of boys born 

 was 106-31. Recent calculations lead to pretty much the same 

 result. Thus, in the years 1872 to 1888, for every 100 girls, the num- 

 ber of boys born in the German Empire was 106-2; in 1871-1885, 

 for every 100 girls, the number of boys born in Prussia was 106-3, 

 in Bavaria 106-4, in Saxony 106, in Switzerland 106-2, in Austria 

 106-6, in Norway 106-4, in Belgium 105-7, and in Italy 107; in 

 1872-1885, for every 100 girls, the number of boys born in Wurtem- 

 berg was 105-1, in Baden 105-5, and in Alsace-Lorraine 106; and 

 in 1876-1885, for every 100 girls, the number of boys in Hungary was 

 105-6, in France 104-3, and in Sweden 106-2. The surprising regu- 

 larity of this phenomenon has given rise to various attempts at ex- 

 planation, but for the present the regular excess of male births must 

 be regarded as a scientific enigma." 



(No. 3): "Since there is a relative excess of males born everywhere, it is 

 probable that migration has produced the preponderance of female population 

 found in some countries." (High). 



(Part 4): "In addition to the factors of birth and mortality, 

 migration has an effect on the distribution of the sexes. In the United 

 States especially, the stream of European immigrants has affected 

 the ratio by increasing the proportion of men. In sex distribution 

 migration, indeed, may become a factor of very great importance in 

 smaller districts and especially in towns, but it is of receding conse- 

 quence in the collective study of great groups of states or entire con- 

 tinents." 



(No. 4): "Migration being on the whole a subordinate factor in sex dis- 

 tribution, and the main factors being the ratios of births and deaths, it is very 

 probable that the female preponderance in population in some lands, and also 

 the approximate equilibrium of the sexes throughout the world, are due chiefly 

 to a higher mortality of males from about the 5th to the 40th years of life, on 

 account of the greater violence, strains and risks involved in the amusements 

 and callings of boys and men as compared with girls and women, during this 

 period of greatest exposure and least discretion." (High). 



(Part 5) : "Beside the ratio of male and female births, the greater 

 infant mortality of males has an important part in sex equilibrium. 

 In the German Empire in the years 1872-1885 the percentage of males 

 among those born alive was 51-3 and of females 48-7, but among the 

 still-births the percentage of males was 56-23 and of females 43-77. 



