663 



emphasize the fact that we have heeii able to detnotistrate this age 

 ill different groups. In tills manner a criterion lias been given to 

 determine in each separate case whether one has to do with a real 

 premature development, or with a normal, though perhaps rajiid 

 one. A meiiarche after the age of ten and a half years is a normal 

 event. As far as the threshold-age of maturity is concerned tliere 

 is no difference between the Jewish and the non-Jewish girls. And 

 yet there is a difference, viz. the greater frequency of the menarche 

 immediately after the threshold has been crossed, so tiiat before 

 the age of 12 the sexual function has begun in 40 °,/„ of the Jewish 

 girls comjiared to 30 "/o '" '''^ non-Jewish blondes, and 18 '/o '" 

 the brunettes. 



It is very curious that after this rapid rise in the variability 

 curve, through which the top is already reached at the age of 1'2, 

 the variation line descends very slowly. Next to a group with 

 accelerated sexual development comes a second with a retarded one. 

 The result is, of course, that the average age of tlie menarche in 

 Jewish girls is not much earlier than in non-Jewish individuals; 

 for among the blondes I found a mean age of 13 years, 5 months, 

 and 17 days, while for the Jewish girls the average was 13 years, 

 3 months, and 24 days. 



The averred precocity of the Jewish girls compared with the rest 

 of the population, seems, therefore, not to exist, for the slight differ- 

 ence which can be discerned by the above methods, is sufTiciently 

 explained by the fact, that the data of the Jewesses, with the ex- 

 ception of a few, refer to inhabitants of towns. I can, therefore, 

 on the ground of my investigation, agree with Fishberg's conclusion 

 that precocity is not a characteristic of the Jewish race. ') 



1) M. FisHBERG. "Die Rassenmerkmale der Juden." Miinchen 1913. 



