MANIFESTED IN HUMAN SOCIETY 109 



and to this tendency the great increase of insanity may 

 be due. There is no necessity for the type to be over- 

 strung, given a well-developed physique. Many of the 

 finest examples of nervous development and nervous 

 energy in our public life are not over-strung because 

 their well-developed nervous systems are founded on 

 well -developed physical frames. As the nervous system 

 appears to direct the distribution of nutrition it would 

 probably have first call on the supply. 



In this connection may be mentioned the fact that a 

 London journal described the Russian ballet dancers 

 as " usually short young women." As their training 

 develops and their performances expend a vast amount 

 of nervous energy, it is possible that this has some effect 

 on their physique, especially as they commence their 

 training very young. It is a significant fact, also, that 

 Pearson finds that tall women are more fertile than short 

 women. Well fed and mentally active people of the 

 towns will be relatively infertile. Well fed and sluggish 

 country people will be relatively fertile. But in the 

 case of tHe* poorer townspeople the effects of greater 

 nervous activity will, in large measure, be counteracted 

 by bad feeding and overwork. 



Of the South African Kaffirs Spencer writes : " Rich 

 in cattle, leading easy lives, and living almost exclusively 

 on animal food (chiefly milk, with occasional flesh), these 

 people were then reputed to have a very high rate of 

 multiplication. Barrow writes : ' They are said to be 

 exceedingly prolific ; that twins are almost as frequent 

 as single births, and that it is no uncommon thing for a 

 woman to have three at a time.' " 1 



The picture drawn by Spencer is a little too rosy. The 

 degree of fertility will probably be chiefly decided by 

 1 Principles of Biology, vol. ii, part vi, chap. xii. 



