THE PLANT CELL. 



CRYPTOGAMIA (non-flowering' plants) 



Non-Vaseulap Cryptogams 



Vascular Cryptogams 

 Pteridophyta 



Thallophyta Bryophyta 



I r I I Heterosporous Homosporous 



I I I 1 types types 



Alg£e Fungi Heijatica- Musci = Hydropteride* =Filices 



SelaginelIe;L' Kquisetine 



Isoeteje 

 PHANEROGAMIA (flowering plants) 



Angiospermse <- 



Gymnospermse 



LycopodiaceK 



Monocotyledons Dicotyledons 



Coniferif Cycadepe 

 (inetaceit 



The arrows show the order in which the table should be read; 

 it indicates that the line of evolution of the Higher Plants has 

 been by way of the Heterosporous Pteridophyta and the Cycadese, 

 certain fossil types probably intervening. 



The dotted line shows the homological connection between the 

 Heterosporous Pteridoph3'ta and the Gymnosperms (the subject of 

 homology will be referred to in detail at the end of Chap. ix.). 

 The chief variations in the structure, etc., of the cell, will be 

 found amongst the Higher Plants — viz., higher ferns, Monocoty- 

 ledons, Dicotyledons, and Gymnosperms (Coniferre), and these will 

 lie the main grou]is used in dealing with plant histology. 



