CHAPTEE II 



GEKM-PLASM AND BODY, THEIK MUTUAL. 

 INDEPENDENCE 



IN the last chapter we discussed two bio- 

 logical principles which, if clearly grasped, 

 greatly simplify an understanding of the 

 process of heredity. These are as follows: 



(1) A sexually produced individual arises 

 from the union of two reproductive cells (or 

 gametes), each of which contains, so far as 

 heredity is concerned, a full material equip- 

 ment for the production of a new individual. 

 Accordingly, the newly produced individual is 

 two-fold or duplex as concerns the material 

 basis of heredity. 



(2) If the new individual becomes adult and 

 forms gametes, the production of these will be 

 attended by a reduction to the simplex or 

 single condition as regards the material basis 

 of heredity. 



27 



