342 GENERAL MORPHOLOGY OF PLANTS 



organs, sperms and eggs; the fertilized egg develops the sporo- 

 phyte, the fern plant which bears the asexual spores. The for- 

 mula may be written as follows : 



Gametophyte ^ )> Fertilized egg Sporophyte asexual 



spores Gametophyte, etc. This formula abbreviated is 

 G < S > FE S asp G, etc. 



Diagram V. Illustrating the life cycle of a fern or Pteridophyte. Course of develop- 

 ment follows the direction indicated by the arrows. Zygote equals fertilized egg. Vegeta- 

 tive multiplication by buds. Note the increase of the sporophyte and decrease of the 

 gametophyte. 



