The Seniors of the Forest 291 



vegetative cell, and beside it, a little chamber full 

 of spermatozoids. And in the larger spore mean- 

 time there is formed a " female" prothallus, which 

 soon grows big enough to rupture the spore-wall 

 and protrudes through the fissure it has made. 



FIG. 82. A larger (" macro") and two smaller (" micro ") spores 

 of Selaginclla martensii (the Lycopodium stoloniferum of florists). 

 All magnified alike to show actual comparative size. 



In this protruding part, archegonia, like those of 

 the fern-prothallus, are formed, and at about the 

 same time the spermatozoids in the smaller spore 

 are ready to seek their affinities, and the spore-wall 

 bursts, setting them free. They are provided with 

 little cilia, which quiver and vibrate like the cilia 

 on the fern-spermatozoid, and by means of these 

 they swim actively over the dewy- or rain-soaked 

 ground, till they find the larger spore and in it 

 the archegonium they have been seeking. 



