x MORPHOLOGY OF ANGIOSPERMS 



CHAPTER PAGE 



VII. FERTILIZATION 143 



Historical resume, 143 Development of pollen-tube, 146 Chala- 

 zogamy, 149 The pollen-tube within the embryo-sac, 151 Dis- 

 charge of pollen-tube, 152 Fusion of male and female nuclei, 

 153 Centrosomes, 153 Double fertilization, 155 Male cell and 

 male nucleus, 160. 



VIII. THE ENDOSPERM . . .165 



Contrast between Gymnosperms and Angiosperms, 165 The 

 fusion nucleus, 166 Endosperm without fusion, 166 Endo- 

 sperm and pollination, 167 Division of fusion nucleus, 169 

 Two methods of endosperm-formation, 171 Function of endo- 

 sperm, 179 Xenia, 179 Morphological character, 181 Nature 

 of triple fusion, 182. 



IX. THE EMBRYO 187 



Monocotyledons, 188 Alisma type, 188 Pistia type, 192 

 Lilium type, 193 Orchid type, 194 Dicotyledons, 196 Cap- 

 sella type, 199 Other types, 200 Degree of development, 205 

 " Pseudo-monocotyledons," 206 Phylogeny of the cotyledon, 

 208 Parthenogenesis, 210 Polyembryony, 213. 



X. CLASSIFICATION OF MONOCOTYLEDONS 227 



Spiral series, 228 Cyclic series, 234. 



XI. CLASSIFICATION of ARCHICHLAMYDEAE 240 



XII. CLASSIFICATION OF SYMPETALAE 252 



XIII. GEOGRAPHIC DISTRIBUTION OF ANGIOSPERMS 261 



Monocotyledons, 262 Archichlamydeae, 266 Sympetalae, 268. 



XIV. FOSSIL ANGIOSPERMS 272 



Monocotyledons, 272 Dicotyledons, 276. 



XV. PHYLOGENY OF ANGIOSPERMS 280 



Are Angiosperms monophyletic I 280 Relation to Gymno- 

 sperms, 283 Relation to Pteridophytes, 285 Theories of alter- 

 nation of generations, 288 Theory of the strobilus, 288 The 

 mutation theory, 292. 



XVI. COMPARATIVE ANATOMY OF THE GYMNOSPERMS AND THEIR ALLIES 296 

 Pteridophytes, 296 Cycadofilices, 300 Cycadales, 304 Ben- 

 nettitales, 306 Cordaitales, 307 Ginkgoales, 307 Coniferales, 

 308 Gnetales, 310. 



XVII. COMPARATIVE ANATOMY OF ANGIOSPERMS 311 



Dicotyledons, 311 Monocotyledons, 314. 



