620 



INDEX 



Phytoplankton, distribution in depth of, 



317. 483, 485, 486, 487, 488, 



518, 519, 521 

 — , predators and, 488, 518, 519 

 — , rate of development of, 519, 520 

 — , vertical gradient of distribution of, 



483,485,486,487,519 

 Phytosociology, see Plant sociology 

 Piassava, 270 

 Picea (Spruce), 98, 102, 142, 173, 174, 



246, 268, 269, 274, 292, 341, 343, 



345, 347, 376 

 P. abies (Norway Spruce), 246, 346 

 P. engelmantiii (Engelmann Spruce), 



376 

 P. glaiica agg. (White Spruce), 346, 



348 

 P. mariana (Black Spruce), 292, 346, 



347, 348 _ 

 P. obovota (Siberian Spruce), 346 

 Pickering, C, 20 

 Pigeon, 1 14 

 — Pea, 258 

 Pigmentation, 27, 29, 33, 35, 38, 41, 43, 



496 

 -^, algal, ecological significance of, 39, 



474-5. 495-6, 512-13, 530-1 

 Pigweed, see Aniarant/iiis retroflextis 

 Pike (Fish), 477 

 Pili-nut, 258 

 Pills, covering of, 264 

 Pimbina, see Viburnum 

 Pimento, 261 



Pincushion Cactus, see Mammillaiia 

 Pine, see Pinus 



■ barrens, 350 



nut, 258 



Pineapple, see Ananas comosus 



Pinguicula (Butterwort), 373 



Pinus (Pine, see also Yellow Pine), 102, 



104, 105, 142, 174, 246, 268, 269, 



^273, 341, 343, 345, 355, 377 

 — , five-needled species of, 80, 252 

 — , geographical data on, 345 

 — , pollen of, 104, 105 



Pinus banksiana (Jack Pine), 346 



P. caribaea (Slash Pine), 352 



P. contorta var. latifolia (Lodgepole 

 Pine), 346, 376 



P. halepensis (Aleppo Pine), 355 



P. insularis, 66, 67 



P. pahistris (Longleaf Pine), 352 



P. pinea (Stone Pine), 355 



P. ponderosa (Ponderosa Pine), 295, 

 376 



P. puniila (Siberian Dwarf-pine), 346 



P. resinosa (Red Pine, Norway Pine), 



349 

 P. rigida (Pitch Pine), 549 

 P. sibirica (Siberian Stone-pine), 346 

 P. strobus (White Pine), 246, 349 



Pinus P. sylvestiis (Scots Pine), 173, 181, 

 200, 246, 327, 346, 574 

 P. sylvestris, Lapponian form of, 346, 



347 



P. taeda (I^oblolly Pine), 352 



P. ivallichiana, 295 

 Pioneer plants, 28, 29, 48, 51, 325, 327, 



328,369,371,456,464,548 

 Pistachio-nut, 258 

 Pistia stratiotes, 484, 485, 504 

 Pisum sativum (Common Pea), 88, 89, 



233 

 Pitch Pine, see Pinus rigida 

 Pitcher-plant, see Sarracenia 



— family, see Sarraceniaceae 



Pityeae, 145 



Place of origin, of plant group, 178 



Plagioclimax, 330, 361, 373 



— , biotic, 360, 361, 363, 456 



Plan of book, 5-7 



Plane-tree, see Platanus 



Planets, other, 127 



Plank-buttresses, 351, 428, 429, 438, 467 



Plankter, 480 



Plankton [see also Phytoplankton), 34, 



93, 318, 320, 325, 333, 473, 479-89, 



518 

 — , flotation of, 479, 483, 517, 518, 521 

 • — , freshwater, 473, 479-89, 480, 481, 



486, 487, 503 

 - — , freshwater communities of, 480-1 

 — , limnetic, 473 

 — , marine, 480, 509, 51°, 5 1 3, 5 1 5. S16, 



517-21 

 — , — , density of, 509 

 — , — , influence on environment of, 



509, 519 

 — , neritic, 474, 480, 514, 520 

 — , net-, 480 



— , pelagic, 473, 480, 520 

 Plant adjustments and applications, 



562-80 

 breeding, 7, 562, 564, 579 



— community, 7, 14, 304, 329, 331-4, 



554. 

 , evolution of, 565 



— diseases, 80, 250-2, 305, 306, 341, 



576 



, distribution of, 80, 120, 248 



250-2 



— dispersal, see Dispersal 



— distribution patterns, 7, 8, 9 



— geographical study, 571-3 



— geography, i, 2, 3, 4, 5, 7, 10, 15, 17, 



, aims of, 3, 4 [19 



, bases of, 14 



, earlier works on, 17, 20-3 



, economic significance of, 3, 560, 



573-9 



, historical, 9 



, physiology and, 175-81, 482 



