106 BRITISH PLANTS 



xerophytes ; some climb, some have succulent leaves, 

 others leaves hoary with hairs ; one has leaves like ivy, 

 another leaves like flax, another leaves like heath ; but 

 the flowers are the same in all. 



In Part II. we have to deal chiefly with biological 

 divisions based upon functional similarities and dis- 

 similarities. Land-plants, for example, will be divided — 



1. According to their Longevity (Chapter XI.). 



2. According to their Frequency of Seeding (Chap- 

 ter XL). 



3. According to their Mode of Growth (Chapter XII.). 



4. According to their Mode of Nutrition (Chapter XIII.). 



