INDEX 



793 



Plasmopara, 432, 433 



Plastids, 11 



Platanaceae, 623 



Platanthera, 746 



Platanus, 623 



Platystemon, 642 



Plectasciueae, 441 



Plectonema, *78 



Pleiochasium, 127 



Plerome, 86 



Pleuridium, 496 



Pleurocarpi, 496 



Pleurocladia, *412 



Pleurosigma, 391, 392 



Plum, Prunus domestica 



Plumbagella, embryo-sac, 572 



Plumeless Thistle, Garduus 



Plumule, 565 * 



Pneumatophores, 167, 246 



Poa, 734 



Pocket- leaves, 185 



Podetium, 471 



Podocarpus, 593 ; ruycorrhiza, 261 



Podophyllum, 638, *639 



Podospora, 442 ; perithecium, *443 



Podostemaceae, 576 



Poisons, 294 



Polarity, 72, 282, 291, *292, 305; 



establishment of, 74 

 Pollen-chamber, 563 

 Pollen grains, 197, 540 

 Pollen sacs, 197, 540, 546 ; cohesion 



mechanisms, 335 ; development of, 



541 



Pollen-ttibe, 201, 541 

 Pollination, 201, 545 ; of flower, 551 

 Polyangium, *385 

 Polycarpicae, 629, 639 

 Polygala, *655 

 Polygalaceae, 655 

 Polygamy, 546 

 Polygonaceae, 621 

 Polygonatum, *719, 725, 726 ; geotropism, 



*345 ; rhizome of, 119 

 Polygoninae, 621 

 Polygonum, *621 ; embryo-sac in, *571 ; 



ovary of, *572 

 Polyhybrids, 322 

 Polypodiaceae, 508 

 Polypodium, 507, 509, *511 

 Polyporeae, 463 

 Polyporus, 465, 467 

 Polysiphonia, 427 

 Polytoma, *399 

 Polytrichaceae, 495 

 Polytrichum, *491, 492, 494, 496 ; 



antheridium, *479 

 Pond-weed, Potamogeton natans 

 Poplar, Populus 

 Populus, 615,^*616 

 Porogamy, 573 



Potamogeton, *720, 721 



Potamogetonaceae, 721 



Potentilla, 663 



Presentation time, 348 



Primula, *686, 687 ; heterostyled flowers, 

 *560 



Primulaceae, 687 



Primulinae, 687 



Pro-embryo, 565, 568, 575 



Promycelium, 455 



Prophase, 23 



Prop roots, 140 



Prosenchyma, 48 



Protandry, 559 



Proteid crystals, 30 



Proteids, hydrolysis of, 267 



Prothallium, 567 



Protococcales, 400 



Protogyny, 559 



Protomastiginae, 381 



Protonema, 475, *476, 490 



Protoplasm, 218 ; movements of, 13, 326, 

 328 ; permeability of, 241 



Protoplasts, 11 ; chemical properties of, 14 ; 

 connections of, 43 ; inclusions of, 27 ; 

 main vital phenomena of, 13 ; origin 

 of the elements of, 21 ; structure of 

 the parts of, 15 



Prunus, *107, *660, *663, 664 



Psalliota, *464, 466 



Pseudo-parenchyma, 437 



Pseudotsuga, 598 



Psidium, 675 

 I Psilophytales, 501 

 I Psilophyton, 501 



Psilotaceae, 502, 527 



Psilotum, 527 



Psychotria, 704, 705 



Pteridium, *498, 509 



Pteridophyta, 496 ; classes of, 5QJ. ; 

 embryo, 498 ; gametophyte, 497 ; 

 heterosporous, 501 ; homosporous, 

 501 ; prothallium, 497 ; sexual repro- 

 duction, 200 ; sporangia, *197, 499 ; 

 spores, 499 ; sporophylls, 499 ; sporo- 

 phyte, 498 ; suspensor, 498 ; vascular 

 bundles, 499 ; vascular system, 105 



Pteridospermtae, 503, 534 



Pteris, *101 ; apex of a root, *132 ; 

 embryo, *497 



Pterocarpus, 673 



Ptyxis, 87 



Puccinia, *456, *457, 458, 459 



Pulvinus, *115, 336, *337, 351 



Pumpkin, Cucurbita Pepo 



Punica, 676, *677 



Punicaceae, 676 



Pure line, 322 



Pycnidia, 443 



Pycuoconidia, 443 



Pycnospores, 443 



