REPRODUCTION, PUBERTY AND LONGEVITY. 237 



the inhabitants live outdoors and drink wine ; the climate of Strass- 

 burg is uneven and cloudy and the people live in the houses and 

 drink beer. M. Raciborski draws the conclusion that the age of 

 puberty is advanced or retarded a little more than a month for 

 each degree of latitude, with the condition that the temperature 

 varies with the latitude. We find this exemplified in the Creoles of 

 Jamaica, who arrive at puberty at from 10 to n years of age, while 

 with the Swedes and Norwegians this stage is delayed till the age 

 of 15 or 16. 



CAUSES INFLUENCING THE AGE OF PUBERTY. 



While the average age of female puberty may be set at about 

 14 years for the central portion of the temperate climate, it may be 

 instructive to look a little more closely at the causes of variation at 

 a definite place. I have previously pointed out that during the 

 adolescent stage the individual is acutely sexual, and that children 

 produced during this period are more intensely sexual in character 

 than those produced at a later stage in life. An individual who 

 has one inherited character more intense than other characters will 

 have that particular character developed at an earlier age in him 

 than it is developed in an ordinary individual. 2 As a consequence, 

 the child of an early reproduction is more likely to arrive at puberty 

 at an early age than one who is produced from old parents, and in 

 cases of successive early reproductions this tendency will be still 

 more strongly marked. We would also have the same result in 

 cases where parents had habitually indulged in sexual excesses for 

 a considerable period prior to the conception of children. We have 

 abundant evidence of this in the cases of the "Jukes" and "Ish- 



(2) It is only necessary, for the proof of this assertion, to compare the 

 characters and aptitudes of our 354 great men with each other. 



