736 



INDEX. 



Silk-cotton tree, 417 



Silver bell, 710 



Siphoneae, 146, 162 



Skunk's cabbage, 439-442 



Slime molds, 83 



Smoke-tree, 707 



Snow covers, 472 



Societies, 522, 526, 527 



Sod-formers, 558, 559, 56^ 



Solanum, 710 



Solidago, 712 



Sourwood, 709 



Spadix, 428 



Spartium, 446 



Spathyema foetida, 438, 662, 703 



Spermagonia, 190 



Spermatophyta, 653 



Spermatophytes, 338 



Sphacelaria, 168 



Sphserella lacustris, 158, 159 



Sphaerella nivalis, 158, 350 



Sphaeriales, 218 



Sphagnales, 248 



Sphagnum, 164, 608-615 



Spiderwort, u, 703 



Spike, 428 



Spinifex squarrosus, 592 



Spirodela polyrhiza, 27 



Spirogyra, 1-5, 13, 14, 60, 72, 136- 



140, 350, 626 

 Sporangia, 178-182 

 Sporangium, 253-258, 281, 290 

 Spores, 225, 256-258, 263, 264, 281 

 Sporobolus asperifolius, 558 

 Sporocarp, 173 

 Sporogonium (spo"ro-go'ni-um), 



224, 231, 233, 234, 237, 238, 239, 

 241, 246, 247, 248 

 Sporophyll, 274, 281, 292 

 Sporophyte (spo'ro-phyte), 225, 226, 



232, 234, 237-239, 241, 242, 250, 



261, 268, 270, 283, 292, 294, 314, 



315, 3i7> 336-339, 340-348, 434 

 Spurge family, 707 

 Squash, 711 

 Staminodium, 446 

 Starch, formation of, 68, 70-74; 



changed to sugar, 77, 78; translo- 



cation of, 73; digestion of, 75 

 Stems, types of, 365-373 

 Stems, woody, structure of, 381-382 

 Stipa spartea, 561 

 Stoma (pi. stomata) (sto'ma-ta), 



42-44, 46 



Strand formations, 586 



Strawberry, 455, 680, 706 



Stress, lines of, 504 



Strophostyles helvola, 591 ?<" " 



Succulents, 394, 395, 580 



Sugar-maple, 685 



Sugar, test for, 75, 76 



Sumac, 707 



Sundew, 133, 610, 706 



Sunflower, 399-401, 712 



Swamp, 606 



Swamp societies, 620 



Sweet gum, 706 



Symbiosis, 85, 86, 92-95, 480 



Synergids (syn'er-gids), 327^330 



Syngencesious, 424 



Synthetic assimilation, 67 



Tamarack swamps, 616 



Tape-grass, 702 



Taraxacum densleonis, 700, 711 



Taxonomy, 652 



Taxus, 534 



Teasel, 711 



Telegraph- plant, 399 . 



Teleutospore, 188 



Temperature, 134, 135, 468, 479, 



501, 507, 623, 624 

 Tetrasporaceae, 161 

 Tetraspores, 173, 174 

 Thallophyta, 653 

 Thallophytes, 352 

 Thallus, 352 

 Thelephoracese, 219 

 Thickets, 516, 530, 704 

 Thistle family, 697, 712 

 Thunderwood, 707 

 Thyrsus, 427 

 Tilia, 708 



Tillandsia, 491, 703 

 Tissue, tensions of, 57-59 

 Tissues, classification of, 363, 364; 



kinds of, 356-359; organization 



of > 35 6 -3 02 

 Toad-flax, 696, 710 

 Tomato, 710 

 Tradescantia, 703 

 Tragopogon, 711 

 Trailing arbutus, 709 

 Trailing wild bean, 591 

 Trametes pini, 90 

 Transpiration, 35-46 

 Tree growth, northern limit, 576, 577 

 Trees, longevity of, 532-534 



