HEREDITY IN MAN" 



363 



mangro or sambo for those with throe. It is also evident from the 

 diagram that mulatto parents have one chance in sixteen of 

 producing a black child and one of producing a white. Individuals 

 of the latter class are called by a number of names, including 



Fig. 200. — Radiograph showing symphalangism in man. The two proximal 

 phalanges in each of the four fingers are fused. (Through the courtesy of 

 Professor R. A. Hefner.) 



pass-for-white and octoroon. Their negroid ancestry is usually 

 plainly evident in other characters than color. 



Polydactyly, Brachydactyly, and Symphalangism. These con- 

 ditions are modifications of the fingers and toes which are 

 dominant over the normal condition. The first is multiplication 

 of the usual number of five digits. An extra thumb or great toe 



