DEVELOPMENT OF PLANTS 



333 



and the other one to the foot (Fig. 230, A, f). The growth 

 of these four cells results at first in the formation of a rather 

 globular sporophyte, but soon the growing point of the young 



Fig. 230. Germination of the gametospore: A, section of archegonium, 

 after fertilization, showing the four-celled stage of the germinating gameto- 

 spore. The cell r by repeated division forms the first root, c forms the first 

 leaf, s forms the stem and / the foot; x, apical cell of prothallium. B, later 

 stage. The young sporophyte rupturing the archegonium or calyptra, 

 lettering as in ./I. 



root grows through the calyptra, turns downward and pene- 

 trates the soil (Fig. 230, B). This is followed by emergence 



Fig. 231. Older sporophyte that has developed two roots, r, and is un- 

 folding the second leaf, /, but still attached to the withering gametophyte 

 or prothallium, p; rh, rhizoids. 



