CONTENTS xxi 



SECOND PART. FORMATIONS AND GUILDS 



CHAPTER I. THE FORMATIONS 



PAGES 



I. Climatic and Edaphic Factors. General type of the vegetation determined by atmo- 

 spheric precipitation. General type of the flora determined chiefly by heat. Details determined 

 by edaphic influences. The formations. Principal and subsidiary members. Distinction between 

 climatic and edaphic formations. 2. The Climatic Formations, i. Classification. Charac- 

 teristics of woodland and grassland. The struggle between them. Invasion of the Malayan 

 forest by the alang-steppe. Degradation of woodland and grassland into desert. Character- 

 istics of deserts, ii. Woodland Climate. Climatic conditions for the existence of trees. Hygro- 

 philous and xerophilous trees. The limits of tree-growth. Brushwood. Characteristics of 

 woodland climate, iii. Grassland Climate. Climatic conditions for the existence of grasses. 

 Characteristics of grassland climate, iv. Meteorological Tables. What they tell and what they 

 should tell. 3. The Edaphic Formations, i. Edaphic Influences in general, ii. Edaphic 

 Formations due to Telluric Water, iii. Open Edaphic Formations. Rocks, gravel, sandy soil, 

 iv. Transition from Edaphic into Climatic Formations. Krakatoa. The volcano Gunter. The 

 Camargue. 4. Life of the Plant-commune in the Formations .... 1 59-1 91 



CHAPTER II. GUILDS 



Introduction. 1. Lianes. Scramblers, Root-climbers, Twiners, Tendril-climbers. Geo- 

 graphical distribution of lianes. 2. Epiphytes. Oecological conditions of life. Transition 

 from the terrestrial to the epiphytic mode of life. Contrivances for ensuring dispersal of seeds. 

 Geographical distribution of epiphytes. 3. Saprophytes. Occurrence in families of plants. 

 Connexion between structure and mode of life. Geographical distribution. Hemisaprophytes. 

 4. Parasites. Hemiparasites and holoparasites. Resemblances to saprophytes. Organs of 

 absorption: haustoria. Occurrence in families of plants. Geographical distribution . 192-206 



THIRD PART. ZONES AND REGIONS 



Introduction 209 



SECTION I. THE TROPICAL ZONES 



CHAPTER I. GENERAL CHARACTERS OF THE TROPICAL 

 CLIMATE AND ITS EFFECTS ON VEGETATION AND FLORA 



1. General Characters of the Tropical Climate, i. Atmospheric Precipitations. Rain. 

 Relative humidity. Clouds, ii. Heat. Temperature of the air. Healing by direct insolation, 

 iii. Lgiht and the Ultra-violet Rays. Intensity of the chemical rays of light. 2. Some 

 General Effects of the Tropical Climate on Plant-life. i. Processes that are chiefly 

 influenced by Heat. Cardinal points. Cases of rapid and slow growth. Transpiration in sun 

 and shade, ii. Physiological Action of Tropical Light on Plants. Protective measures against 

 intense light. Decomposition of chlorophyll. Position of foliage-leaves. Photic ration of shade- 

 plants, iii. Physiological Action of Atmospheric Precipitations on Plants. The controlling influ- 

 ence on the character of the vegetation and the periodic processes. Ombrophily and ombrophoby. 

 3. The Floristic Character of the Tropical Zones. Survey of the megathermic group of 

 forms ................ 211-240 



CHAPTER II. THE PERIODIC PHENOMENA OF VEGETATION 

 WITHIN THE TROPICS 



1. General Prevalence of Periodic Phenomena in the Functions of Plants. No 



absolute period of rest. Rest only for some processes. Occurrence of periodicity in tropical 

 vegetation. 2. Periodicity in the Vegetative Domain, i. deaf-fall. Frequency of periodic 



