Spitsbergen, manuring by birds in. 402 



— , potato grown in, 231 



— , seaweeds in, 537 



— , soil polygons in, 396 



Splitters, 202 



Sponge, 2, 129 



— , freshwater, 495 



Spora, 99 



Sporangium {pi. sporangia), 41, 42, 44, 



45, 49, 56, 57, 59, I34 

 Spore, 27, 41, 45, 49, 51, 52, 56, 57, 



59, 98, 99, loo-i, 131, 327, 434, 



490 



— dispersal, 99-101, 117, 125, 252 



— ejection, 121, 125 



— germination, 52, 56, 117, 520 



— liberation, 52 



— output of Fungi, 45, 100, 125 

 Spores washed from air by rain, 106 

 Sporobolus, 361 

 Sporophyll, 57, 59 

 Sporophyte, 49, 53, 55, 57, 59, 62, 63, 



69 

 Spray, saline, 527 

 Spring annuals, 355 



— deposits, 547 



— flowering habit, 340 



— flush communits', 374, 547 



— maxima of Algae, 481, 518, 519, 



520 

 moss, see Fontinalis 



— plankton, 481, 519, 520 



— rainfall, 289, 360 

 Sprouting, of hedge after clipping, 13 

 — , of pasture after close grazing, 13 

 Spruce, see Picea 



— gum, 273 



Moose biome, 211 



Spurge, see Euphorbia 



— family, see Euphorbiaceae 

 Squash {see also Cucurbits), 234, 258 

 Squillj, 264 

 Squirrels, 116, 424 

 Squirting Cucumber, see Ecballium 



elateriiim 

 Stabilization of sand-dunes, 328, 371, 

 458, 548, 549. 566 



— of sere, 324 

 Stacks, 550 

 Stage lightning, 59 

 Stages of hydrosere, 325, 326, 353, 



502-5 



— of xerosere, 325-6, 327, 328, 372 

 Stamen. 68, 70, 71 

 Stanford, E. E., 252, 281 

 Stanley, O. B., 281 

 Star anise, 262 



Starch, 29, 53, 56, 255, 260, 269 

 Static evolution, 132 

 Steam. W. T., xviii, 169, 172 

 Stebbins, G. L., 179, 181 



INDEX 631 



Stellario (Chickweed), 78 



S. humifusa (Low Chickweed), 399 

 S. media agg. (Common Chickweed), 

 120, 249 



Stem structure. Monocotyledon, 70, 73 



, Dicotyledon, 71, 73 



Stems, drugs from, 264 



Stenohaline Algae etc., 474, 508, 523 



Stenoionic Algae, 523 



Stenophotic plants, 474 



Stenothermic (stenothermal). Algae etc., 

 474, 499, 522, 525, 528 



Stephoiioptera, 502 



Steppe, 162, 360, 361-3, 365, 413, 445, 



454, 

 — , forest, 363 

 — , mountain, 413. 470 

 Stereocaulon, 392 

 Stereuni iffine, 44, 45 

 Stewart, M. N., 335 

 Stictaceae, 421 

 Stigma, 68, 70, 71 

 Stilbocarpa polar's, 420 

 Stimulants, 263, 264 

 — , chemical, 13 

 — , heart, 263 

 Stimulus, directional, 13 

 Stinging Nettle, see Urtico and U. dioica 

 Stinkhorn, see Ithyphalliis 

 St/pa (Feather-grass), 361, 365 

 Stolon, 69, 400 



Stoma (/)/. stomata), 14, 76, 82, 180, 452, 

 Stone fruit, 113, 258 [505 



— Pine, see Piniis pinea 

 Stones, Algae living within, 494 

 Stonewort, see Chara and Nitella 

 Stoneworts, see Charales 

 Storage of food by plants, 32, 33, 35, 39, 



78, 87, 90, 91 



Stored food-reserves, 69, 546 



Stories (strata) in forest vegetation, 338, 

 339, 424-8, 434, 440, 462, 468, 469 



Stork's-bill family, see Geraniaceae 



Strains, artificial, 564 



Stramonium (see also Datura stramo- 

 nium), 264 



Stranglers, 431, 435, 436 



Strangling Fig, see Ficus 



Strata, see Stories 



Stratal (layer) society, 334 



Stratification (cyclical) in lake water, 

 477, 486, 487 



— in soil, 297, 299, 301 

 • — in vegetation, 291, 338-9, 425, 426, 



, tropical forest, 425. 426 [468 



Strawberry', see Fragaria and F. grandi- 



flora 

 Streams, benthos of, 498-9 

 — , dispersal by, 107 

 — , erosion by. 543 

 — , fertile land deposited by. 544 



