490 THE STORY OF PLANT LIFE 



" Botanischer Jahresbericht," Jost. 



" Genera Plantarum," Bentham and Hooker. 



"Topographical Botany," H. C. Watson. 



Ibid., Supplement, A. Bennett, 1903. 



" Cybele Britannica," H. C. Watson. 



" Cybele Hibernica" (2nd edition), Moore and A. G. More 



1898. 

 " Irish Topographical Botany," R. L. Praeger. 



5. Fossil Botany. 



The classification of plants is intimately connected with 

 their phylogeny or race history, which, though to be unravelled 

 by the study of ontology or the embryology of plants, has 

 not so far been settled by this method, as the vegetable 

 embryo has not as yet revealed the same indications afforded 

 by animals. Therefore the appeal to phylogeny is the 

 greater in the case of plants, especially as comparative 

 anatomy in this case again does not so far supply the answer 

 satisfactorily. Plants are more plastic, and conceal original 

 characters more completely than animals. 



There has been, moreover, a great advance made in the 

 knowledge of fossil plants and ancient floras during the last 

 ten years, largely through the labours of British botanists 

 — Williamson, Scott, Seward, Kidston, Stopes — and more 

 recently through those of Wieland, in America; Zeiller, 

 Laurent, Lignier, Renault, on the Continent. 



Two main considerations prompt an inquiry into the 

 geological history of plants — a desire to discover the origin 

 of the British flora, and the origin of angiosperms; and 

 related to the latter also is the question of the origin of 

 gymnosperms, and that of monocotyledons and dicotyledons. 



Two eras have largely contributed hints upon these ques- 

 tions — the Carboniferous and the Jurassic (and Cretaceous). 



