724 
Ophioglossum, external characters, 4313 
spore-producing members, 4473 spore- 
mother-cells, 451 (Figs. 250, 251); ana- 
tomy, 458 (Figs. 256, 258, 259); embryo, 
466 (Fig. 260); prothallus, 464; crotalo- 
Pphoroides, 4313 opacum, 431; vulgatum, 
431 (Fig. 235); Bergianum, 433; bulbo- 
SUM, 4333; nudicaule, 4333 lusttanicum, 
423; pendulum, 435; palmatum, 435 
(Figs. 238, 239); sémplex, 441; tnter- 
medium, 441; reticalatum, 439, 448 (Fig. 
246); 451 (Fig.-250). 
‘Orientation of embryo variable, 666. 
‘Origin of members as new structures, 659 ; 
objections answered, 680. 
Osmunda, 530 (Fig. 293); sporangia ot, 
532, 535 (Figs. 296 bis, 296); anatomy 
of, 536 (Figs. 298, 299) ; embryology of, 
540; reduced leaves of, 239; vegadis and 
" javanica, 169 (Fig. go). 
‘Osmundaceae, external characters, 530 (Fig. 
293); spore-producing members, 533; 
anatomy, 536; embryology, 540; phyletic 
position of, 654 (Fig. 354). 
Osmunidites, 539. 
‘Overtopping, 135, 136. 
Pachytheca, 228. 
Palaeophytology, 
limitations, 229. 
Palaeopteris hibernica, 582. 
Palacostachya, 150 (Fig. 81); vera, 375 
(Fig. 203); morphology of cone, 384 
» footnote. 
Parts, independent origin of, 183. e 
Pecopteris, 528; (Dicksonites) Pluckenett, 
528; dentata, 519 (Fig. 287); usta, 520. 
Pellia, 266 (Fig. 128). 
Periblem, 178. 
Periodic reduction, 84. 
Leronospora, 68. 
Phascum, 282 (Fig, 139). 
Phragmidium, 69. 
Phyllanthus, 126. 
Phylloglossum, 297 (Figs. 145, 146); spor- 
angium of, 315; embryology of, 352, 355 
(Fig. 189); detached leaf-traces, 199 ; 
protocorm of, 225. 
Phylloids (Lignier), 136. 
Phyllopodium, 629. 
Phyllosiphonic structure, 139, 198; state, 
may be derived from cladosiphonic, 487-8; 
secondary, 648. 
evidence of, 227; its 
INDEX 
Phyllotheca, 150, 167, 372 (Fig. 197), 384. 
Phylogeny of Filicales, 652. 
Physcomttrella patens, 36, (Fig. 20). 
Physcomitrium, 280 (Fig. 137). 
Physiological experiment, 6; a check on 
phyletic speculation, 236. 
Phytonic theory, anatomical aspect of, 188 ; 
of Delpino, 135. ; 
Picea excelsa, ovule of, 41 (Fig. 27). 
Pilularia, 551. 
Pinakodendron musivum, 304. 
Pinus Laritcio, germination of pollen, 42 
(Fig. 28). 
Platycerium, 631. 
Platyzoma, 553. 
Plerome, 178. 
Pleuromota, 220 (Fig. 114), 302 (Fig. 151); 
strobilus of, 304 (Fig. 154). 
Podostemaceae, symmetry of, 201. 
Polarity, 203; of embryo variable, 666 ; 
inversion of, 675. 
Pollen-mother-cells, 49 (Fig. 32). 
Polygonum, ovary of, 44 (Fig. 30). 
Polyphyletic development, 11. 
Polypodium, 628; phyletic position of, 656 
(Fig. 354) 3 pesectatum, 616; vulgare, 23, 
28, 214 (Figs. 7, 12, 110); symmetry of 
seedling, 214 (Fig. 110). 
Polysiphonia, 67, 81. 
Polysporangiate state, 113. 
Polystelic type, 189. 
Polystichum angulare, v. pulcherrimum ; 
apospory in, 55 (Fig. 37). 
Polytrichaceae, stem-structure, 195-6. 
Polytrichum, 281. 
Porella, 265 (Fig. 126). 
Precocity of cotyledon, 670, 671; of root, 
672. 
Primitive shoot, 716. 
Progressive metamorphosis of Goethe, 157, 
251. 
Prohepatic type of Lignier, 137, 216. 
Prothalli of Lycopodium, 340; saprophytic, 
342; subterranean, 343. 
Prothallus of Fern, 25. 
Protocalamariaceae, 373. 
Protocorm, 181, 223, 253, 6723; in Phanero- 
gams, 224; of Lycopods, 351. 
Protostelic state in primitive Ferns, 647.- 
Protoxylem, peripheral in Lycopodium, 328; 
central in Sedaginella, 332. 
Psaronius, 507, 526, 528. 
Pseudobornia, 373, 424. 
