THE EVOLUTION OF PLANTS 55 



have learnt that the remains are vegetable as well 

 as animal: so that the terms should properly be 

 palseobiotic instead of palaeozoic, and so forth. 

 What, then, is " time's abstract and brief chronicle " 

 thus furnished us ? 



In palaeozoic times there certainly existed many 

 kinds of algce, the simplest known order of green or 

 chlorophyll-containing plants. Here, at the outset, 

 is a fact of far more than botanical or palaeo- 

 botanical importance : for we know that the animal 

 kingdom, in general, ultimately depends for its food 

 entirely upon thechemical powers which thepossession 

 of chlorophyll confers upon the green plant. It was 

 therefore to be expected that the advent of the green 

 plant should prove to be as early as the early stages 

 of animal life ; and so it was. . . . We also find 

 remains which show that the fungi — those lowly 

 plants which contain no chlorophyll — already 

 existed in the primary or palaeozoic period ; whilst 

 students competent to judge accept as proved the 

 existence of bacteria — the lowest order of fungi—- 

 in those times. Many plants which correspond to 

 our present mosses and ferns also existed ; but there 

 is no trace whatever of the fioiverivg-plants, a term 

 which properly includes what we call trees, all 

 of which bear unmistakable though usually very 

 inconspicuous flowers. 



The remains of the giant ferns of the later ages 

 of the primary period now serve mankind in a 

 thousand ways under the name of coal. 



In the later stages of the mesozoic period we find 

 the first signs of the higher kinds of plants which 

 rapidly carried all before them, almost put an end 



