23 



Each chromosome, or idant, composed of many 

 ids. 



Each id composed of smaller unites, the deter- 

 viiuauts, one for each independently variable 

 part of the organism. 



Each determinant composed of the ultimate 

 unites of living matter, biopJiors. 



Control of the cell by the nucleus and the ne- 

 cessity for biophors. 



The id in ontogeny. 



The division of the id of germ-plasm into 



an active id of somatic idioplasm and an 



id of reserve germ-plasm. 

 Growth and multiplication by division of 



the determinants and ids. 

 The qualitative and quantitative divisions of 



the active ids. 

 The migration of the biophors of the active 



determinants from the nucleus into the 



cell-body. 

 Fate of the reserve germ-plasm. 



The effect of amphimixis. 



The homologous determinants in the ids may 

 be homodynamous or heterodynamous. 



Hence a possible struggle of the ids in 

 ontogeny. 



Significance of the polar bodies. 



The maturation of the Qgg and the forma- 

 tion of the spermatozoon preceded by the 

 doubling of the idants and ids. 



The first subsequent division (first polar 

 spindle) reduces this number by half. 



The second division (second polar spindle in 

 the Q^g^ reduces the remainder by half. 



Advantage of two reducing divisions in in- 

 creasing variability. 



Origin of variations. 



