CHAPTER XIII 



THE MESOZOIC GYMNOSPERMS 



I. Cycadophyta 



Our studies have so far been almost entirely limited 

 to plants of Palaeozoic age ; in order to carry out our 

 plan of directing attention to discoveries of fundamental 

 botanical importance, we have now to give an account 

 of the Mesozoic Cycadophyta, a group among which 

 some of the greatest triumphs of Paleobotany have 

 been won. 



From the Trias onwards to the Lower Cretaceous, 

 the Mesozoic vegetation maintained, on the whole, a 

 very uniform character, widely different from that of 

 the preceding Palaeozoic period. Throughout the 

 earlier Mesozoic ages true Ferns were abundant, 

 more so, no doubt, than in the preceding period ; 

 Conifers, often much resembling recent types, had 

 become a dominant group, and the family now 

 represented solely by the Maidenhair tree {Ginkgo) 

 was of considerable importance. The most striking 

 feature of the vegetation, however, in all parts of the 

 world, was the abundance of plants belonging to the 

 same great class with the recent Cycadaceae, now so 



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