REPRODUCTION BY SPORES 31 



by means of seeds. Among the so-called spore-bearing 

 plants we included the algae, the fungi, the liverworts, 

 the mosses, the ferns and their kindred. We now know 

 that the higher plants, that is, those with flowers, also 

 bear spores, and that the flower itself is a spore-producmg 

 organ, as well as a seed-producing organ. This will be 

 discussed at more length later. 



6. How Spores Behave. They are reproductive bodies 

 looking wholly to the next generation. As compared with 

 other cells in the mother plant the spores are usually 

 highly resistant. Often they float around in the dry air 

 without hurt. Many of them will stand cold much below 

 the freezing point of water. In many of the parent plants 

 these conditions would mean death. On the other hand, 

 the swimming spores are usually remarkably delicate and 

 easily destroyed. 



While the spore usually does not have the power of 

 growing in the ordinary way, nor of dividing into two 

 spores as the bacteria divide, it has a definite manner of 

 returning to life and activity. Usually the cell wall around 

 it is a little tough. When conditions are favorable, as for 

 example, after one of these spores has been floating 

 around in the atmosphere and comes into a moist place 

 where its food is abundant, it takes up water and begins 

 to swell. It then sends out through the softened or 

 broken wall a delicate tube of its protoplasm, surrounded 

 by a thin membrane. This tube is the beginning of a 

 new plant. This process by which the spore starts the 

 new plant is called germination. 



Germination differs very much as to time. In some 

 kinds of spores germination may begin within a few hours 

 after the spore escapes. This is true of the ordinary 

 spores of the bread molds. One may readily see these 

 spores germinate, and begin to form the fine threads of 

 the mold, by placing on an ordinary glass slide a decoction 

 of bread or fruit juice and dusting it with spores. If this 

 is placed in a moist chamber and watched at frequent 



