CHAPTER VIII 



THE FERNS 

 Fronds ; Fructifications; Anatomy 



We have now reached the fourth of the classes, or 

 phyla, under which the Vascular Cryptogams — recent 

 and fossil- — naturally group themselves. This fourth 

 phylum is that of the Filicales, or Ferns in the widest 

 sense ; among all the Pteridophyta it is this stock 

 which holds the strongest position at the present day. 

 The Lycopods are unimportant now, compared with 

 what they once were ; the Equisetales survive only in 

 one single genus ; the Sphenophyllales disappeared alto- 

 gether about the close of the Palaeozoic period. 1 But the 

 Ferns form one of the most prominent groups among 

 living vegetation, numbering, on the most moderate 

 computation, not less than 60 genera and 3000 

 species. 



Until quite recently all palaeobotanists held that the 

 Ferns were even more important in Palasozoic times 

 than they are at present, in fact that they were the 

 dominant class of plants at that period. According to 



1 Unless we regard the Psilotaceae as their last surviving remnant ; see 

 the concluding chapter of the book. 



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