294 Field, Forest, and Wayside Flowers 



to maturity. After this interval of rest, the tube 

 makes its way to the macrospore, pierces its deli- 

 cate wall, and enters the neck of an archegonium. 

 Here it finds a little globule of protoplasm, similar 

 to that which is contained by the archegonium of 

 a fern. One of the generative cells from the 

 pollen-tube fuses with this globule, and after their 

 union is complete creative life begins to mould 

 their combined substance into a little cone-bearer. 



The second " generative cell" of the pine-pollen 

 seems to be a mere understudy. It comes down 

 the pollen-tube into the ovule, but the most recent 

 investigators agree that it does not enter an 

 archegonium, and that, after a brief interval it 

 melts away, as it were, and disappears. It may be 

 a reminiscence of a now obsolete method of fer- 

 tilization practiced by the pine's ancestors. 



Fern, selaginella, pine, and rose seem to repre- 

 sent successive stages in the dwindling of the pro- 

 thallus. That of the fern is a perfect plant, with 

 green leafy surface and serviceable root-hairs. It 

 comes out into the great world, supports itself in- 

 dependently there, and reaches, sometimes, the 

 ripe age of two years. That of the selaginella is 

 minute, and spends its brief life almost encom- 

 passed by the spore. That of the pine is highly 



