INDEX 



1063 



Pistia, 833 

 Pisum, 992 



— sativum, 476, 1041 

 Pith, 889, 909 



Pits, II 



— bordered, 464 



— simple, 464 

 Pityoxylon, 660 

 Placenta, 489 

 Plagiotropic organs, 837, 840 



— shoots, 962 

 Plane, 844 



Plankton, 145, 148, 185 

 Plant Kingdom, 5 



— Pathology, 2 

 Plantaginaceae, 1026 

 Plantago, 1030 



— 7najor, 459 

 Plasma membrane, 8 

 Plasmalemma, 14 

 Plasmodesma, 1 1 

 Plasmodiophora ; akaryote stage, 198 



— cytology, 197 



— Plasmodium, 195 



— reproduction, 197 

 Plasmodiophora brassicae, 193 

 Plasmodiophorales, 192 

 Plasmodium, 188, 189, 195 

 Plasmopara nivea, 234, 235 

 Plastids, 10, 16 

 Plastochrone, 852, 987 

 Platanus, 951 



— orientalis, 844, 1005 

 Plectascales, 249 

 Plectenchyma, 155, 271 

 Pleomorphism, 187 

 Plerome, 451, 794 

 Pleurococcus, 366 



— reproduction, 75 

 Pleurococcus naegelii, 74 

 Pleuromeia, 607 

 Pliny, the Elder, 40 

 Plum, 840 



Pneumatophores, 818 

 Poa alpina, 944 



— secunda, 790 

 Podocarpineae, 659, 695 

 Podocarpus, 454, 659, 678 

 Podophyllum, 918 

 Podosp'haera, 256, 257 

 Podostemaceae, 828 

 Poiseuille's Law, 897 

 Poison Ivy, 933 

 Polarity, 836, 846 

 Pollen chamber, 726 



— grain, 640, 674 



— sac, 640, 699, 720 



— tube, 637, 681 

 Pollination, 637 



— drop, 700 



Polycarpic perennials, 834 

 Polycycly, 508, 564 

 Polyembryony, 689 

 Polygonaceae, 991, 993 

 Polygonatum, 814, 947 



— 'rmdtiflorum, 933. 934 

 Polygonum amphibium, 1012 



— hydropiper, 992 



— viviparum, 944 



Polyploid nucleus, 23 



Polypore of Birch, 312 



Polyporus ; sporophore structure, 3 1 4 



Polyporus betulituts, "^12 



— dryadeus, 3 1 7 

 Polysiphonia, 182, 183 



— antheridium, 163 



— asexual reproduction, 167 



— carpogonium, 163 



— sexual reproduction, 163 

 Polysiphonia fastigiata, 102, 163, 164, 340 



— fibrillosa, i6u 



— nigrescens, 160 



— violacea, 1G4, 166 

 Polystely, 565, 920 



Polytrichum ; sexual reproduction, 433 



— sporogonium, 435 

 Polytrichum commune, 416, 430, 436 

 Pol>Tcylic stem, 714 



Pontederia cordata, 979 

 Poplar, 841 

 Populus, 827 



— candicans, 971 



— nigra var. italica, 840 

 Portulaca, 1019 

 Potamogeton, 798, 874, 879, 992 



— nutans, 875 



■ — perfoliatus, 994 



Potato, 937 



Pothos, 963 



Potonie, 653 



Powdery Mildew, 253 



Prantl, 45 



Preston, 12 



Prickles, 470, 870 



Prickly Pear, 925 



Priestley, 799, 868, 876, 891 



Primary roots, 787 



— vascular tissues, 883 



— wall, II, 27 

 Primitive spindle, 830 

 Primula, 880, 10 17, 1030 



— auricula, 920, 921 

 Primulaceae, 1026 



Principal plane ; in Cycas seed, 727 



Prismatic cells, 593 



Procambial strand, 663 



Procambium, 802, 854 



Proliferating flowers, 840 



Prophase, 19 



Prophylls, 988 



Prosenchyma, 453 



Protaxis, 655 



Protococcus viridis, 74 



Protocorm, 744 



Protoderm, 794 



Protomitosis, 197 



Protonema, 415, 428, 436 



— secondary, 439 

 Protophloem, 858, 860 

 Protoplasm, 8 

 Protoplasmic connections, 27 



— membrane, 14 



— permeability, 15 



— utricle, 15 

 Protostele, 557 



Protoxylem, 483, 858, 859. 863 

 Prumnopitys, 963 



Prunus, 827 



