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CHAPTER XX. 



THE CARBONIFEROUS SYSTEM— Continued. 

 THE FLORA OF THE COAL FORMATION. 



I have already endeavoured to introduce the reader into the jungles 

 and forests of Carboniferous Acadia ; but in order that he may fully 

 appreciate the nature of the wondrous vegetation of that ancient time, 

 the producer of all our stores of mineral fuel, it will be necessary that 

 we shall pass in review the several genera of Coal formation plants, and 

 endeavour so to restore them that, in imagination, we may see them 

 growing before us, and fancy ourselves walking beneath their shade. 

 While thus endeavouring to introduce the ordinary reader and the 

 student of Geology and Palaeontology to an acquaintance with the 

 Coal Flora, I shall take advantage of the abundant material within my 

 reach to restore some of the species more completely than has hitherto 

 been possible, and thus to present to geologists what T trust may 

 prove a more full and accurate synopsis of the leading features of the 

 Carboniferous Flora than any at present accessible. 



The modem flora of the earth admits of a grand twofold division 

 into the Phcenogamous, or flowering and seed-bearing plants, and the 

 Cryptogamous, or flowerless and spore-bearing plants. In the former 

 series, we have, first, those higher plants which start in life with two 

 seed-leaves, and have stems with distinct bark, wood, and pith — the 

 Exogens ; secondly, those simpler plants which begin life with one seed- 

 leaf only, and have no distinction of bark, wood, and pith, in the 

 stem — the Endogens ; and, thirdly, a peculiar group starting with two 

 or several seed-leaves, and having a stem with bark, wood, and pith, 

 but with very imperfect flowers, and wood of much simpler structure than 

 either of the others — the Gymnosperms. To the first of these groups or 

 classes belong most of the ordinary trees of temperate climates. To the 

 second belong the Palms and other trees found in tropical climates. 

 To the third belong the Pines and Cycads. In the second or Crypto- 

 gamous series we have also three classes, — (1.) The Acrogens, or ferns 

 and club-mosses, with stems having true vessels marked on the sides 



