MOSSES AND FERNS 



7Z 



2. The Life Cycle in a Moss. This Hfe history is more 

 complex than anything we have yet described, but it will 

 well repay careful study. 



a. The Germination of 

 the Spore. If we start 

 with a spore, we find 

 that after a longer or 

 shorter period of rest 

 it germinates. This 

 means that the soft, 

 inner living part 

 swells, bursts the old 

 spore w^all, and sends 

 out a tube. This tube 

 becomes green, like a 

 filamentous alga, man- 

 ufactures food, grows, 

 and branches abund- 

 antly. The whole 

 thing at this stage is 

 called a protonema, 

 the word referring to 

 its thread-like appear- 

 ance. This stage is 

 not usually noticed. 



b. Budding. Bud-like out- 

 growths next appear at 

 various points on these 

 threads. These buds do not grow into new threads 

 like the old ones from which they spring, but di- 

 vide in such a way as to form upright stalks or 

 stems. Each of these stalks develops root-like 

 structures and leaves, lengthens considerably, and 

 becomes one of the leafy moss plants with which 

 we are all acquainted. 



c. Formation of Gametes and Fertilization. At the 



Fisiire 18. A young moss plant 

 (magnified I arising from the proton- 

 ema. From Coulters Plant Life 

 a>td Plant Uses. 



