LIST OF ILLUSTRATIONS xxiii 



FIG. PAGE 



154. Heterangium Grievii. Restoration of a portion of the stem . 403 



155. ,, ,, Transverse section of stem . . 404 



156. ,, ,, Transverse section from outer part of 



stele . . ... . 405 



157. Heterangium Grievii. Corresponding longitudinal section 406 



158. ,, liliaeoides. Radial section . . . 412 



159. Sphenopteris elegans. Ribbed stem 416 



160. ,, ,, Part of frond . 417 



161. Neuropteris heterophylla. Part of vegetative frond 426 



162. Alethopteris lonchitica. Part of frond . 427 



163. Medullosa anglica. External view of stem 430 



164. ,, ,, Transverse section of stem 431 



165. , , , , Part of transverse section, showing steles 



and leaf-traces ..... . 432 



166. Medullosa anglica. Two leaf-trace bundles from the outer cortex 



of the stem ... ..... 434 



167. Medullosa anglica. A. Transverse section of petiole. B. 



Vertical section of leaflet ...... 436 



168. Sutcliffia insignis. Transverse section of the stem and leaf-bases 448 



169. Neuropteris heterophylla. Seed . . 451 



170. Trigonocarpus Parkinsoni. Diagrammatic median section in 



the plane of the wing . . . 454 



171. Trigonocarpus Parkinsoni. Diagrammatic transverse section 



through the body of the seed . 455 



172. Trigonocarpus Parkinsoni. Diagrammatic transverse section 



through the micropyle . . 455 



173. Stephanospermum akenioides. Upper part of pollen -chamber . 458 



1 74. , , , , Multicellular pollen - grains in 

 pollen-chamber . . .... 459 



175. Pecopteris Pluckeneti. Fragment of a fertile pinna with seeds . 467 



176. Calamopitys Saturni. Transverse section of stem . . . 478 



177. Calamopitys fascicular! s. Transverse section of central part of 



stem . ... 481 



178. Cycadoxylon robuslum. Part of transverse section . . . 484 



179. Ptychoxylon Levyi. Transverse section of a decorticated 



stem . 488 



180. Cycadospadix milleryensis. Fructification . . 493 



181. A. Poroxylon Edwardsii. Transverse section of stem. B. 



P. Boyssetii. Transverse section of young stem . . . 503 



182. Poroxylon Edwardsii. Transverse section, showing xylem-strands 505 



183. Poroxylon Boyssetii. Transverse section of petiole 507 



184. Poroxylon Sutclijffii. Transverse section of stem . 511 



185. Rhaidocarpus subtunicatus. Transverse section of seed 513 



186. Pitys antiqua. From a transverse section of stem 516 



187. Dorycordaites. Restoration . ... 520 



188. Cordaites lavis. Branch (restored) bearing the large spathulate 



leaves and inflorescences . . . 5 22 



189. Cordaites. Part of transverse section of stem .... 527 



190. Cordaites (Araucarioxylon) Brandlingii. A. Radial section of 



middle part of stem. B. Inner part of wood . S 28 



191. Amyelon radicans (probably a root of one of the Cordaiteae) . 531 



192. Cordaites. Leaves in transverse section. A. C. angulosostriatus. 



B. C. rhombinervis. C. C. lingulatus . 533 



193. Cordaianthus Penjoni. A. Longitudinal section of male catkin. 



B. Stamens . . S37 



