MODEEN PEOBLEMS 317 



culture.^ Whether a differential birth-rate results or not in a 

 differential contribution to the next generation depends on 

 whether there is a differential survival rate, and if so, whether it 

 compensates for or not the differences in the birth-rate. The 

 following extract from the Eeport of the National Birth-Eate 

 Commission throws light upon this point. Using material pro- 

 vided by the Eegistrar-General for England and Wales giving the 

 births for 1911 classified according to the occupation of the father, 

 the following is the position : 



* Classifying into groups arranged in descending order of social 

 grade we have : 



Births per 1 ,000 married vuiles 

 Social Class. aged under 55 years. 



The rate of mortality in the first year of life is also provided in 

 these groups, and follows the same order, viz. 76-4, 106-4, 112-7, 

 121-5, 152-5. If, however, we multiply the birth-rate by the 

 difference between unity and the proportion of deaths, i. e. the 

 proportion of survivals in the first year, the resulting effective 

 birth-rates are still in the same order, viz. 110, 118, 136, 139, 181, 

 after the hazards of the first twelve months have passed. We 

 must conclude, therefore, that the initially higher birth-rate of 

 the lower classes is not so reduced by heavier infant mortality 

 that their effective birth-rates are brought into approximate 

 equality with those of the wealthier classes. We have no material 

 allowing us to extend the comparison to later years of life ; but 

 equally we have no reason to suppose that such an extension 

 would change the order.' ^ 



All available evidence goes to support this conclusion, namely, 

 that the higher the social status the lower is the fertility, and that 

 this initial difference is not removed by subsequent differential 

 mortality. This is apparently true not only for England but also 

 for other countries in which the economic situation is similar, and 

 is a relatively recent phenomenon.^ 



' Heron, Drapers^ Company Research Memoirs, No. 1, 1906. See also Stevenson, 

 loc. cit. - Tlie Declining Birth-rale, p. 9. 



s It is also noticeable in India (Wattal, loc. cit., p. 24). It will be remembered 

 that in Denmark in the latter part of the mediaeval period there was some slight 

 tendency according to Rubin for marriage to be postponed among the very highest 

 social class ; among the independent class generally marriage in those days, how- 

 ever, not only took place earlier tlian now but earlier than in the lower grades of 

 society. 



