720 
Cynosurus, 128. 
Cystopteris, phyletic position of, 655 (Fig. 
354); belbefera, 19 (Fig. 3). 
Cystopus, 68. 
Cytological distinction of alternating genera- 
tions, 61. 
Cytopteris fragilis, 615 (Fig. 341). 
Danaea, 94 (Fig. 49), 505 (Fig. 275); sorus 
of, 512 (Figs. 278, 281, 283, 286); anatomy 
of, 525; embryo of (Fig. 277); alata, 
symmetry of, 212 (Fig. 106). 
Danaettes, 523 (Fig. 290). 
Davallia, 613; phyletic position of, 655 
(Fig. 354); Grifithiana (Fig. 66), 613 
(Fig. 339); Aymenophylloides, 615 (Fig. 
340). 
Decentralisation in Mosses, 286. 
Dennstaedtia, 613 (Fig. 332 dis); D. 
rubiginosa (Fig. 333), (Fig. 65), 601, 
616, 597 (Fig. 332 42s); irregular arrange- 
ment of sporangia of, 598; solenostely in, 
600 (Figs. 333 A-C); apzzfolia (Fig. 65); 
Davallia series, 613 ; phyletic position of, 
655 (Fig. 354). 
Dennstaedtiinae, 595. 
Deparia, phyletic position of, 655 (Fig. 354). 
Dermatogen, 178. 
Desmids, 70. 
Diacalpe, 617. 
Dichotomous branching of stem in Ferns, 
626; theory of origin of shoot, 630. 
Dichotomy in Fern leaves, 627, 628. 
Dicksonia, 592 (Figs. 330, 331); phyletic 
position of, 655 (Fig. 354); Bearomerz, 
193 (Fig. 97); punctiloba, 190 (Fig. 95). 
Dicksonieae, subdivision of the family, 591. 
Dictyostele, 190. 
Dictyostelic state in Ferns, 647. 
Dictyota dichotoma, 66, 8t. 
Diphyscium, symmetry of, 205 (Fig. 104). 
Diploid phase, 47, 52. 
Diplotmema, 554. 
Dipteridinae, 618, solenostely in, 621. 
Dipteris, 618 (Figs. 343-346). 
D. conjugata, mixed sorus, 621: phyletic 
position of, 656 (Fig. 354). 
Dispersal of spores, 645. 
Divergent series, 10. 
Dorsiventral construction, 201. 
Dorsiventrality of shoot, 208 ; derivative in 
Ferns, 626. 
Double leaf-trace, 689, footnote. 
INDEX 
Equisetales, 366; external characters, 368 ; 
spore-producing member, 377; anatomy, 
385; embryology, 392; summary, 395. 
Equisetum, 94 (Fig. 50); anatomy of, 191 
(Fig. 96); reduced leaves of, 239; spor- 
angial development, 377; sterilisation in, 
378; stelar structure of, 386 (Figs. 211, 
212, 213); maximum, 149 (Fig. 79); 
368 (Fig. 193); 370 (Fig. 194); pratense, 
367 (Fig. 192) ; 373 (Fig. 196); scirpoides, 
176 (Fig. 91); sylvaticum, polystachyum, 
370 (Fig. 194); Azemale, 369; anatomy 
of seedling, 391; root apex (Fig. 92); 
limosum, 369 ; arvense, 370; sylvaticum, 
379; myriochaetum, 370. 
Elaterophore, 90, 266. 
Elaters, 262. 
Eligulatae, 291 ; embryology of, 340. 
Embryo, biological study of, 181; dependent 
on prothallus, 238; of LZgzdsetum, 392 
(Fig. 214). 
Embryology, 173, 251; initial and continued, 
1743 primary in Bryophytes, 660; con- 
tinued in Vascular Plants, 678; of Pterido- 
phytes, 663; segmentation of embryos, 
664 (Fig. 355); of Ferns, 649; of 
Filicales, 649; of Lycopods, 340; of 
Ophioglossales, 489; of Ophioglossum 
vulgatum, 466 (Figs. 260, 260 42s); of 
O. moluc and O. pendulum, 466; 
of Botrychium virginianum, 469 (Fig. 261) ; 
of B. Lunaria, 470 (Figs. 262, 263); of 
B. obliquum, 471 (Figs. 264-266); of 
Helminthostachys, 473 (Fig. 267). 
Enation of leaf, 141; of leaves from axis, 
680; objections answered, 681. 
' Endothecium, 272, 278, 285. 
Enumerations of spores, 641. 
Ephemerum, 208. 
Eucharidium, 96 (Fig. 54). 
£u- Davallia, mixed sorus, 613. 
Eusporangiate Ferns, relatively primitive, 
495. 
Epibasal tier, 666. 
Exogenous roots, 219. 
Experimental Morphology, 6. 
' External characters of Filicales, 625. 
Extra-prothallial swellings, 673. 
Factors of advance, 85. 
Fegatella (Conocephalus), 260. 
Fern, life history of, 14; vascular skeleton 
of, 15; sorus of, 20; spores of, 20; 
