596 INDEX 



Deadly Amanita, see Amanita phalloides 



— Nightshade, 263 



Death, 69, 75, 77, 97, 250, 303, 305, 482 



DeCandolle, A., 22, 223, 252 



Decay etc., 27, 278, 280, 303, 497-8, 539 



Deception Island, 418 



Deciduous habit, 337, 338, 339, 340-4 



— perennials 452 



— summer forest, 332, 333, 337, 338, 



339. 340-3, 376, 377 



, mixed, 338, 339, 340-2 



, types of, 340-3 



Decomposition, arrest of, 498 

 — , by Bacteria, 303, 497, 539 

 Deep-rooting habit, 76, 82, 84, 85, 450, 



451,458 



sea system, 511 512, 538-40 



water forms of Diatoms, 483 



Defensive adaptations, 218 



Deficiency diseases, 79-80 



Deflected succession, 330, 363, 465 



Delesseria sinuosa, 537 



Deltas, 454, 542, 544 



Depletion of algal population, 482-3 



Deposition of calcium carbonate, 130, 



132, 497, 529, 547 

 Depositional features (landforms), 542, 



543, 544, 545, 547, 55° 

 Depressions, 327, 348, 361, 362, 366, 



367, 383, 384, 391, 393, 416, 547 

 Depth of water, Algae and, 475, 495, 

 496, 503> 522, 530, 537 



, chlorophyll and, 496 



, green plants and, 475, 496, 



503, 527, 530, 537 



, photosynthesis and, 474-5 



Deriv-ed savanna, 465 

 Deschampsia antarctica, 417, 421 

 Desert, 16, 83, 85, 87, 91, 93, 213, 246, 



316, 318, 333, 364-8, 376, 449-54 

 — , ' alkali ' {see also Salt desert), 366, 



369 



— and semi-desert, areas of, 213, 556 



— annuals, 93, 365, 451 

 — , cold, 316, 414 



— communities, 11, 366-8, 449-54 

 — , dew in, 451 



— Melon, see Acanthosicyos horrida 



— mesophytes, 452 



— , mud medallions in, 368 



— perennials, 366, 452, 453 



■ — plants, adaptations of, 83, 85, 93, 360, 

 450,451,452 



, deep rooting of, 84, 85, 450, 451 



, high osmotic value of cell-sap of, 



, transpiration of, 452 [452 



— , rainfall etc. of, 364-6, 449-50 

 scrub, 364, 448 



— soil, 365, 366, 368, 452 

 — , spread of, 213, 307 



— steppe, 365 



Desert vegetation, 83, 93, 365, 366-8, 



.449754 

 Desiccation, resistance to, 78, 100, 526 

 Desmarestia, 538 

 Desmids (Desmidiales), 31, 481 

 — , arctic, 478 

 — , general account of, 31-2 

 — , oligotrophic etc. water and, 318, 



477, 501 

 — , Palaeozoic, 132 

 — , planktonic, 479, 481 

 Destructional landforms, 542, 543-51 

 Deterioration of climate, post-Miocene, 

 Detritus, colonization of, 372 [160 



Devonian period, 129, 130, 132, 133, 



135, 138, 145, 146 



Charales, 132 



— forest landscape, 147 



Dew {see also Precipitation), 289, 451 

 Diaspore, 97 



Diatomaceous earth, 34, 279, 497 

 Diatoms, see Bacillariophyceae 

 Dichotoniosiphon tuherosiis, 496 

 Dicotyledones (Dicotyledons), 68, 71, 



73, 276, 355, 365, 427, 431 

 — , fossil, 143, 144, 145, 150 

 — , herbicides and, 276 

 Dictyota, 36, 37 

 Didyiniiini, 42 

 Diels, L., 23, 197 

 Diffuse area, 188 



Digestion, germination and, 115, 117 

 — , seeds and, 114, 115 

 Digitalin, 264 

 Di'aitan'a (Crab-grass), 249 

 Dill, 262 

 Dinoflagellates (Dinophyceae, Peri- 



dinians), 34, 35, 478, 501, 516 

 — , flotation of, 518 



— in freshwater plankton, 480, 481 

 — , general account of, 34-5 



— in marine plankton, 515, 516, 517, 

 — , nutrition of, 35, 501, 520 [518 

 — , photosynthesis of, 35 



— , summer forms of, 476 



Dinophyceae, see Dinoflagellates 



Dioscorea (Yam), 231, 258 



Diospyros ebeuum (Ebony), 247 



Diphtheria, 26, 279 



Diploid, 179, 204 



Dipterocarpaceae, 247 



Dipterocarpits tubercidatus (Eng., Ira), 



Disclimax, 330, 331, 359 [467 



Discontinuity, types of, 188-97 



Discontinuous range (distribution), 55, 



188, 190, 192-7 

 Disease, control of, 576, 579 

 — , extermination by, 250—1 

 — , treatment of, 265 

 Diseases, deficiency, 79 

 ■ — , human, 26, 27, 279 



