322 THE STUDY OF ANIMAL LIFE CHAP, xv 

 recapitulation of phylogcny, or the evolution of the 



race.' 



(d) Organic Continuity. In a subsequent chapter on 

 heredity, which simply means the relation of organic 

 continuity between successive generations, we shall explain 

 the fundamental idea that the reproductive cells owe 

 their power of developing, and of developing into organisms 

 like the parents, to the fact that they are in a sense con- 

 tinuous with those which gave origin to the parents. A 

 fertilised egg-cell with certain qualities divides and forms 

 a " body ' in which these qualities are expressed, dis- 

 tributed, and altered in many ways by division of labour. 

 But it also forms reproductive cells, which do not share 

 in the upbuilding of the body, which are reproductive cells 

 in fact because they do not do so, because they retain 

 the intrinsic qualities of the original fertilised ovum, 

 because they preserve its protoplasmic tradition intact. 

 This being so, it is natural and necessary that these cells, 

 liberated in due time, should behave as those behaved 

 whose qualities they retain. It is thus inevitable that 

 like should beget like. 



