xyizn)® 



xif(2n) ® 



xyizm 



^E xi/(4n) 



Tig. 79. 

 Formation of a diploid protonema (2n) by regeneration from a 

 2n sporophyte of a normal, monoecious moss. By self-fertilization 

 a 2n gametophyte gives rise to a tetraploid or 4n sporophyte. By 

 regeneration from the latter a tetraploid gametophyte is produced. 



