X CONTENTS. 



PABT V.- WOUNDS AND DISEASES-cow^. 



CHAPTER II. DISEASES. 



SECTION I. INTRODUCTORY REMARKS. 



a : PAGE. 

 Duration of Plant Life Definition of Disease Struggle for Existence 



Factors influencing the Relations existing between Organisms Sapro- 

 phytes Competitors, Parasites, Symbionts Symptoms of Disease 

 Disease rarely due to one Factor alone Knowledge required for 

 Investigation of Diseases Sub-division of the Subject . , . 176183 



SECTION II. INFLUENCES OF OTHER PLANTS ON PLANT- 

 DEVELOPMENT. 



(a) PLANT COMPETITORS. 



Deodar and Blue Pine Teak and Bamboos Trees and Grasses Trees and 



Strobilanthes Climbers Epiphytes ...,,, 183 186 



(&) PLANT PARASITES. 



PhytophtJiora infestans PhytophtJiora omnivora Fames annosus Armil- 

 laria mdlea Tramcies Pini Puccinia graminis Mcidium montanum 

 Orobanche indica Cuscuta reflexa Loranthus longiftorus Parasi- 

 tism of Santalum album 186 202 



(c) PLANT SYMBIONTS. 



Lichens Bacteria and Leguminosce Mycorhizas Distant Symbiosis 



between Green and Non-green Plants Decay of Wood . . . 202 205 



SECTION III. INFLUENCES OF THE SOIL ON PLANT-DEVELOPMENT. 



Necessary Salts in suitable Condition and Quantities Poisonous Sub- 

 stances Necessary Water and Oxygen Accumulation of Starch in 

 Leaves indicates Root Trouble 205 208 



SECTION IV. INFLUENCES OF THE ATMOSPHERE ON PLANT- 

 DEVELOPMENT. 



Extremes of Temperature Effects of Excessive Heat Of Excessive Cold 

 Effects of Light Of Excessive MoistureOf Winds Of Poisonous 

 Substances Lightning 208 216 



SECTION V. EFFECT OF FIRE. 



Effect of Fire Necessity of studying Indirect Effect of each Factor . . 216217 



