TETRAPLOIDS 



125 



by Elie and Emile Marchal by artificial means. Each 

 moss plant has two generations, a haploid protonema 

 stage (gametopliyte) that produces eggs and sperm-cells 

 and a diploid stage (sporophyte) that produces asexually 



® ® XiTi) 



XiTl) 



xin) 



XyiZn) Sporophytt 



Gametophyte 



Protonema 



© y(n) ©xm) 



Fig. 78. 

 Normal life cycle of dioecious moss. 



