686 



BOTANY OF THE LIVING PLANT 



of the cell : 18 (Fig. 9), 29 ; its im- 

 portance in syngamy or fertilisa- 

 tion, 557 ; nucleus and heredity, 

 560 ; structure of resting nucleus, 

 560 ; somatic division of (mitosis), 

 562 (Figs. 428, 429) ; tetrad divi- 

 sion of (meiosis), 563 (Figs. 430- 



433). 



Nutrition, autotrophic or hetero- 

 trophic, 22 (Chap, viii.) ; of Bac- 

 teria, its classification, 450. 



Nutritive lacket, a layer of nutritive 

 tissue surrounding the embryo-sac 

 in Gamopetals : 316 (Fig. 235). 



Nymphaea, floating leaves of, 212. 



Oat, analysis of, 660 ; origin of, 661. 



Obconical expansion in Ferns, and 

 Palms, 596. 



Obconical form, problem of, 589 ; 

 in sporelings, 591 ; in stems of den- 

 droid plants, 590 (Fig. 446) ; in 



Ferns, 593. 597 ( Fi S s - 140. 453) I 



supply to buds big and small, 595, 



600. 

 Odontoglossum, mycorrhizic infection 



of, 234 (Fig. 162). 

 Oedogoniales, 365. 

 Oedogonium, 365, 366 (Fig. 271). 

 Oidium-condition, of Mucor, 415. 

 Onion, bulbils of, 246 ; analysis of, 



655- 

 Onoclea, fertilisation of, 503 (Figs. 



395> 396). 



Onygena, sporadic occurrence of, 395. 



Oogonium, the organ in Algae and 

 Fungi, which contains one or more 

 female gametes, or ova ; 352 ; of 

 Fucus, 384 (Fig. 288) ; of Oedo- 

 gonium, 366 (Fig. 271) ; of Vau- 

 cheria, 370 (Figs. 275, 276) ; of 

 Oomycetes, 399, 410 (Figs. 296, 



Oomycetes, 399 (Chap, xxv.), 402, 



447- 

 Oospore, of Pythium, 405. 



Oosporeae, aquatic origin of, 411. 



Open bundle, one possessing active- 

 cambium, 53. 



Operculum, the lid which falls away 

 from the ripe capsule in Mosses, 

 469 (Fig. 364). 



Ophrydeae, mycorrhizic germination 

 of, 233 (Fig. 161). 



Opium Poppy, 626. 



Orchidaceae, 611. 



Orchids, epiphytic, 191 ; endotrophic 

 mycorrhiza of, 231 (Figs. 159, 160, 

 161, 162). 



Orchis, meiomery in, 269 ; flower of, 



612 (Figs. 459, 460). 

 Organic material, formation of new, 



4, Chap. viii. 

 Organographic factors, combination 



of, 602. 

 Orobanche, parasitism of, 226 (Fig. 



153). 

 Orobancheae, 221. 



Oryza (Rice), analysis of, 660 ; 

 origin of, 661. 



Oscillatoria, 376 (Fig. 279 a). 



Osmotic control, upset by shock, 

 164. 



Osmotic phenomena of cells, 34. 



Osmotic pressure, 34. 



Osmunda (Royal Fern), 483 ; apex 

 of, 493 (Fig. 383). 



Ovary, the part of the pistil contain- 

 ing an ovule or ovules, Chap, xvi., 

 p. 288 : superior, where the ovary 

 is borne by the elongated recep- 

 tacle above the other parts, 271 

 (Fig. 195) ; inferior, where it 

 appears sunk in the shortened re- 

 ceptacle, and below the outer parts, 

 272 (Figs. 197, 198). 



Ovule, the megasporangium of flower- 

 ing plants, which ripens into the 

 seed : 294 (Figs. 216, 217) ; of 

 Pine, 534 (Figs. 422, 423) ; mega- 

 spore retained within, 539. 



Ovuliferous scale, of Coniferae, 534 

 (Fig. 422). 



Ovum, or egg, the female gamete, 

 294 (Fig. 216), 298 (Fig. 219), 305 

 (Fig. 226), 306 (Fig. 227), 353 ; of 

 Pine, 536 (Fig. 424) ; of Selagin- 

 ella, 518 (Fig. 412) ; of Fern, 502 

 (Fig. 394) ; of Moss, 468 (Fig. 363) ; 

 of Riccia, 474 (Fig. 370) ; of Fucus, 

 384, 385 (Figs. 287, 288) ; of Oedo- 

 gonium, 366 ; of Pythium, 398 

 (Fig. 296) ; retention of, in arche- 

 gonium, 549, 550. 



Oxidases, 137. 



Oxygen, given off in photosynthesis, 

 120 (Fig. 80) ; absorbed in respira- 

 tion, 135 (Fig. 87). 



Paleae, inner chaffy bracts of 



the Grasses, 616, 617 (Fig. 464), 



658. 

 Palaeozoic Lycopods, 521. 

 Palisade parenchyma, 72 (Fig. 47), 75 



(Fig. 49), 76 (Fig. 51). 

 Palm, stem of, 51 ; mechanical 



construction in stem of, 182 ; 



subdivision of leaf of, 189. 



