1216 PHYSIOLOGY 



It has been suggested that a very large number, if not all, of the charac- 

 ters of an individual might be brought under this law. This might be done 

 by indefinitely subdividing the characters, but the question would then 

 become beyond the limits of analysis or experimental investigation. There 

 is no doubt that many qualities are subject to Mendel's law, and that their 

 study will be of considerable assistance in guiding the efforts of our breeders 

 and horticulturists in the formation of new varieties desirable for their 

 value to man. In respect of many qualities the Mendelian law seems to 

 fail. Thus in man the progeny of a cross between a white and black race 

 are more or less intermediate between the two and vary according to the 

 amount of black and white blood introduced in succeeding generations. 

 Definite black and white individuals are not produced, but merely individuals 

 of various degrees of brownness. 



