I 86 



HEREDITY AND EUGENICS 



The brain convolutions in duplicate twins have 

 also been compared. For example, Sano (191 6) 

 studied the brains of stillborn twin boys. One boy 



Fig. 34. — ^TwiNs from Battle Creek, Michigan. 



They were separated when three years of age, and have always 

 lived apart. Even their best friends cannot distinguish 

 them when they meet. 



was somewhat larger throughout than the other, 

 and this applied also to the brains, the larger brain 

 being more highly developed, with more sulci. But 



Fig. 35. — Twin Sisters from Romanshorn, Switzerland. 



there was a very remarkable similarity in the dis- 

 position of the furrows, and all the differences were 

 of secondary importance, thus indicating the in- 

 heritance of similar mentalities. 



