CHROMOSOMES AND SEX 



383 



?LAMT LIFE CYCLE 



N 



\ 



\ 



/ 



CAMLTES ^- 



V 



hOMOTHALUC BRYOPHYTE 



ANIHAL LlfE CYCLL 





HLTLBOTHALUC BRYOPHYTEl 



^ j niCRo- 



HOMOPHYTIC SEED PLANT 



HETEROPHYTIC SEED PLANT 





Fig. 217.— Diagrams of life cycles of several types. The first diagram is a modification of 

 one by SchafTner (1923c). {After Sharp, 1925). 



