CHAPTER II 



THE BRTOPHYTA 



THE step which we are about to take, in passing on 

 to our next type, carries us across one of the widest gaps 

 in the Vegetable Kingdom. So far, the plant, in the 

 ordinary sense of the word, has in all cases been 

 represented by the sporophyte generation. We have 

 always found that the stage of the life-cycle, lying 

 between fertilisation and spore-production, is that in 

 which the chief vegetative development is attained. 

 The other stage, namely, that which succeeds spore- 

 production and precedes fertilisation, has up to this 

 point appeared as a comparatively insignificant organism, 

 hardly recognisable as a distinct generation in the 

 Phanerogams or Selaginella, though maintaining a more 

 independent position in the Perns and Horsetails. 

 Henceforth we shall find the relative proportions of 

 the two generations reversed, the chief vegetative 

 growth taking place in the sexual stage, corresponding 

 to the prothallus of the higher plants, while the 

 sporophyte is on the whole less highly developed, and 

 serves for little more than the mere production of spores. 

 The sub-kingdom, then, with which we have now to 

 deal, is characterised by the occurrence of a sharply 

 defined alternation of generations, in which the sexual 



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