X 



CONTENTS 



CHAPTER II 



STEMS 



PAGE 



Herbaceous stems 233 



Cross-section, spigelia stem 233 



Ruellia stem 235 



Powdered horehound 237 



Powdered spurious horehound 237 



Insect flower stems 241 



CHAPTER III 



WOODY STEMS 



Buchu stem 242 



Mature buchu stem 242 



Powdered buchu stem 245 



CHAPTER IV 



BARKS 



White pine bark 248 



Powdered white pine bark 250 



CHAPTER V 



WOODS 



Cross-section quassia 254 



Radial-section quassia 254 



Tangential-section quassia 258 



CHAPTER VI 



LEAVES 



Klip buchu 260 



Powdered klip buchu 262 



Mountain laurel 264 



Trailing arbutus 264 



CHAPTER VII 



FLOWERS 



Pollen grains 270 



Non-spiny- walled pollen grains 273 



Spiny- walled pollen grains 273 



Stigma papillae . - 274 



