172 HEREDITY IN RELATION TO EUGENICS 



O^nop 



All daugl)ttrs 

 normal. TJumerous 

 descendants 



2dau.N.( 

 4 sons 



Idau.N 

 d5on5 



Fig. 152. — Pedigree of a family showing prolapsus of the uterus (females) 

 and sterility. Inherited like the absence of a character, with probable consan- 

 guinity in marriage. Bronardel, 1900. 



usually due to an inheritance in the processes that go to 



determine the form and size of the skeleton. 

 a. Achondroplasy is characterized by relatively short 

 limbs, a condition in man like that in 

 the Ancon sheep, dachshund and some 

 bull-dogs. The condition is rare and so 

 we have few if any full pedigrees but 

 enough is known to indicate that it is 

 inherited, as in the case cited by Pouchet 

 and Leriche (1903), Fig. 153, and it is 

 probably due to an abnormal positive 



I 



ii 





Fig. 153.— Pedigree 

 of achondroplasy (black f actoi. 



Sd lSiche ^Zr^"" ^' ScoUosis.— The dissymmetry of the 



trunk accompanied by a curved ' ' spine ' ' 

 is a fairly common condition. That there is an hereditary 

 tendency to it cannot be doubted in view of its frequent 



