200 THE STORY OF THE EAETH AND MAN. 



tion of this point, I may refer to the fact that Car- 

 ruthers, in a recent paper, catalogues twenty-five 

 British species belonging to eight genera a fact 

 which markedly characterizes the British flora of the 

 Mesozoic period. These plants will therefore occupy 

 a prominent place in our restoration of the Mesozoic 

 landscape, and we should give especial prominence to 

 the beautiful species Williamsonia gigas, discovered 

 by the eminent botanist whose name it bears, and 

 restored in his paper on the plant in the " Linnaean 

 Transactions." These plants, with pines and gigantic 

 equisetums, prevailed greatly in the earlier Mesozoic 

 flora, but as the time wore on, various kinds of 

 endogens, resembling the palms and the screw-pines 

 of the tropical islands, were introduced, and toward 

 its close some representatives of the exogens very 

 like our ordinary trees. Among these we find for 

 the first time in our upward progress in the history 

 of the earth, species of our familiar oaks, figs, and 

 walnut, along with some trees now confined to Aus- 

 tralia and the Cape of Good Hope, as the banksias 

 and " silver-trees," and their allies. In America a 

 large number of the genera of the modern trees are 

 present, and even some of those now peculiar to 

 America, as the tulip-trees and sweet-gums. These 

 forests of the later Mesozoic must therefore have 

 been as gay with flowers and as beautiful in foliage 

 as those of the modern world, and there is evidence 

 that they swarmed with insect life. Further, the 

 Mesozoic plants produced in some places beds of coal 



