CONTENTS IX 



PAGE 



2. Spore-producing members 190 



Microsporangium 191 



Megasporangium 194 



3. Gametophytes ■ . . 203 



Female gametophyte 203 



Male gametophyte 206 



Fertilization 209 



4. Embryo • . . . . 210 



5. History and distribution 215 



6. Relationship to other gymnosperms 216 



• Literature cited 217 



Chapter VI. Coniferales (Pinaceae) .220 



1. Vegetative organs 222 



Vascular anatomy 228 



Leaf . 235 



2. Spore-producing members 238 



Microsporangium ........ 240 



Megasporangium 244 



3. Gametophytes 259 



Female gametophyte 259 



Male gametophyte 272 



Fertilization 284 



4. Embryo 287 



Proembryo 288 



Suspensor and embryo 295 



5. Distribution . . 301 



6. History 303 



7. Interrelationship of tribes 308 



8. Relationship to other gymnosperms ..... 309 



Chapter VII. Contferailes (Taxaceae) 313 



I. Vegetative organs 315 



Vascular anatomy 315 



Leaf .... 317 



