7 6 



REPRODUCTION AND LIFE HISTORY. 



I) R 



R 



Heredity may be defined as the relation of genetic 

 continuity between successive generations, and inheritance 

 as all that the organism is or has to start with in virtue 

 of this hereditary relation. Development is the expression 

 or realisation of the heritable qualities which have their 

 physical basis in the germ cells, and it presupposes an 

 appropriate environment of nutrition, "liberating stimuli," 

 and "nurture" in the widest sense. What the organism 

 becomes is the resultant of two components, inherited 

 "nature" and external "nurture." 



