GENERAL SUCCESSION OF PLANTS IN TIME. 1 487 



Not only are the ordinary Exogens now the leading forms of plant- 

 life, but many of the Upper Cretaceous types belong to genera now 

 existing. We may therefore regard the Upper Cretaceous period as 

 marking " the advent of the modern flora of the temperate regions 

 of the earth " (Dawson). It follows that the Tertiary floras, regarded 

 generally, more or less closely resemble those now in existence, this 

 resemblance being especially shown in the fact that the predominant 

 forms of plant-life are now the Angiosperms, and, more particularly, 

 the Dicotyledons. 



