MORPHOLOG Y. 



the sexual phase of the plant (gametophyte) was the prominent one, 

 and consisted of either a thallus or a leafy axis, but in either case it bore the 

 sexual organs and led an independent existence; that is it was capable of ob- 

 taining its nourishment from the soil or water by means of organs of absorp- 

 tion belonging to itself, and it also performed the office of photosynthesis. 



560. The spore-bearing phase (sporophyte) of the liverworts and mosses, 

 on the other hand, is quite small as compared with the sexual stage, and it is 



li 



ft 



Fig. 312. 



Young embryo of fern (Adiantum concinnum) in enlarged venter of the archegonium. S, 

 stem ; L, first leaf or cotyledon ; Jf, root ; F, foot. 



completely dependent on the sexual stage for its nourishment, remaining at- 

 tached permanently throughout all its development, by means of the organ 

 called a foot, and it dies after the spores are mature. 



561. Now in the ferns we see several striking differences. In the first 

 place, as we have already observed, the spore-bearing phase (sporophyte) of 



