INTRODUCTION 3 



Fossil botany or pdcEohotany deals with all the 

 foregoing features in the past, the study of extinct 

 plants. It assists the knowledge derived from a 

 study of present-day forms and their distribution, 

 that is to say geographical botany, in unravelling the 

 mysteries of evolution, a study which takes us back to 

 the origin of forms, and deals with heredity, varia- 

 tion, hybridism, natural selection, Mendelism, the 

 study of mutations, and leads us ultimately to the 

 germ-cell and the chromosomes, and their behaviour 

 under mitosis or other modes of cell-division. 



This last study, a branch of cytology, but just 

 begun as it were, in conjunction with embryology, or 

 the study of the plant in its earliest stages, appears 

 to be at the moment the most promising field for 

 research. 



In the introductory volume some general facts 

 were stated as to the habitats of plants, flowering 

 seasons, the habits of plants, the mechanism of 

 the flower, pollination, seed dispersal and classifica- 

 tion. No more was attempted than a general sketch 

 of the subject, but it is hoped that enough was said 

 to arouse interest in those for whom the book was 

 specially intended. 



In these two volumes it is proposed to deal with 

 some other features of plant-Hfe in a similar manner, 

 viz. : 



*2. The cells, tissues, organs and their office, etc. 

 Transporting and elaborating elements. 



* I. Divisions of the subject (ante). 



