INDEX. 



733 



Opuntia, 559 

 Opuntiales, 708 

 Orchidacese, 665, 703 

 Orchidales, 665, 703 

 Orchids, 442 

 Oscillatoria, 589 

 Oscillatoriaceae, 163 

 Osmosis, 13-20 

 Osmundaceae, 295 

 Ostrich fern, 279 

 Ovule, 302, 321, 334, 421 

 Oxalis, 707 

 Oxycoccus, 709 

 Oxydendrum arboreum, 709 

 Oxygen, 63, 110-113 



Pacific forests, 538 



Palisade cells, 41, 43 



Palmaceae, 702 



Palmales, 702 



Palms, 408 



Palustrine forest, 537 



Pandanales, 702 



Panicum scribnerianum, 559 



Panda nus, 702 



Pandorina, 160, 350 



Panicle, 427 



Panicum amamm, 599 



Panicum halophilum, 599 



Panicum repens, 599 



Papaverales, 652, 676, 706 



Papilionaceae, 423, 682, 707 



Parasites, 83, 84, 86, 527, 628 



Parasitic fungi, nutrition of, 86-90 



Parenchyma, 50, 356, 363 



Parietales, 687, 708 



Parkeriacete. 296 



Parmelia, 96 



Parmelia contigua, 602 



Parsley family, 692 ; =carrot family, 



Parthenogenesis, 184 [708 



Partridge berry, 711 



Pea, 683, 707 



Pea family, 682, 707 



Pear, 456, 682 



Peat moors, 578, 607 



Peat moss, 608 



Pediasirum, 161 



Pelagic plant societies, 627-629 



Pellia, 164 



Pellonia, 405 



Peltigera, 94, 95 



Pepo, 456 



Pericycle, 360 



Peridineae, 166 



Perigynous, 425 



Perisperm, 331, 332 



Perisporiales, 217 



Peronospora, 183, 215 



Peronosporales, 215 



Persimmon, 710 



Peucedanum fceniculaceum, 562 



Peucephyllum schattii, 571 



Pezizales, 217 



Phacidiales, 217 



Phseophyceas, 167 



Phaeosporales, 171 



Phallales, 219 



Phloem, 50-52, 360, 361, 363 



Phlox family, 710 



Phoradendron flavescens, 84, 705 



Photic region, 621, 628 



Photosynthesis, 67, 68, 70, 117, 622^1 



Phycomycetes (Phy // co-my-ce / tes) , 



214, 215 

 Phyllidium, 371 

 Phyllcclades, 373, 395 

 Phyllotaxy, 375, 384 

 Physical condition of soil, 475, 476 

 Physical factors, 465-476 

 Physiography, 479 

 Phytolaccacea?, 705 

 Phytomyxa leguminosarum, 92 

 Phytophthora, 182, 184, 215 

 Pickerel weed, 626, 703^ 

 Pilularia, 296, 627 

 Pinales, 216, 653 

 Pine, white, 297-310 

 Pinguicula vulgaris, 610 

 Pinu3 divaricatus, 602 

 Pinus scopularum, 560 

 Pinus strobus, 602, 653 

 Piperales, 704 

 Pisum sativum, 683 

 Pitcher-plant, 610, 706 

 Pith, 50 



Plains' formations, 559 

 Plankton, 621 

 Plant-food, sources of, 81 

 Plant-formations, 515-528 

 Plant-substance, analysis of, 79, 80 

 Plantaginales, 711 

 Plantago, 711 



Plasmolysis (plas-mol'y-sis), 19 

 Plasmopara, 183, 215 

 Plectascales, 217 

 Plectobasidiales, 220 

 Pleurococcaceae, 161 



