LIVEEWOKTS 121 



the gametophyte throughout its existence, or, at least, 

 for part of its life. The sporophyte, when ripe, produces 

 spores from which gametophytes appear. This alterna- 

 tion of generations will appear more clearly to the reader 

 when we come to study concrete examples; for the 

 present the following manner of statement will be of 

 some assistance : 



Sexual Generation. Asexual Generation. 



Gametophyte Embryo 



Antheridia Archegonia Sporophyte 



\ / J 



Embryo Spore 



(from which gametophyte arises) 



In the Bryophytes (Gr. hryon, moss), which embrace 

 the Liverworts and Mosses, the gametophyte may be 

 thalloid or leafy; it lives independently; it has no true 

 roots: the sporophyte bears no leaves, and remains 

 attached to the gametophyte throughout its existence. 



The Liverworts, or Hepaticse, are unfortunately 

 named. An Italian botanist, Micheli, early in the 

 eighteenth century gave the name to a species on account 

 of its fancied likeness to a liver, and it has stuck to the 

 group in spite of the fact that the majority of the species 

 have not the slightest resemblance to that organ. 

 About 4,000 species are known to science, yet the group 

 as a whole, although so numerous and in every way 

 interesting, has not received the general attention that 

 it so richly deserves; many amateur botanists hardly 

 recognize its existence. This ignorance of the Hepaticse 

 is probably due, to a large extent, to the fact that most 

 species are very inconspicuous and require searching 

 for; besides, the searcher has to have a good idea of 



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