INDEX 



553 



Smoke tree, 438* 



Smuts, 259* 



Social plants, 4-47 



Soft bast (sieve tubes), 61-63* 



Soil, arid, zonation, 476-478* 



Solomon's seal, parallel-veined leaf 

 of, 89* 



Sorus, 313 



Spatulate, App. I 



Species, 153 



Sperm, 166, 183*, 204, 212 



Spermagonia, 262* 



Spermatia, 262* 



Spermatophyta, 354-401* 



Spermatophyte, 354-401* 



Spermatophytes, 400 



Sphaerella, 180-182* 



Sphagnales, 290*, 291* 



Sphagnum, 290*, 291* 



Spike, 133, 134* 



Spine, 416*, 417* 



Spiral vessel, 62* 



Spirogyra, 166* 



Sporangium, 185*, 204, 313, 314* 



Spore, 166 



Spore case, 313 



Spore formation of ferns, 313 



Spore fruit, 321*, 322 



Sporidia, 259*, 261*, 271 



Sporophyll, 314, 315* 



Sporophyll, arrangement of, in 

 flowers, 394 



Sporophyte, 220, 277. 299, 318 



Sporophyte, evolution of, 402-404 



Sporophyte, origin of, 349 



Spot fungi, 253, 254 



Spreading growth, 43* 



Spring spores of wheat, 261* 



Spruce, Douglas, 493, Plate XII 



Spur, fruit, 83*. 84* 



Squash seed, section of, 5* 



Stamen, 123-131*, 358, 368*, 369, 

 377*, 378*, 379, 380 



Stamen, parts of, 127* 



Staminate flower, 124* 



Standard, 125* 



Starch, 9-11*, 25, 107-110 



Starch disappears during germina- 

 tion, 10 



Starch in leaves, 107-110 



Starch making, rate of, 109, 110 



Stem, 15-33*, 40-79* 



Stem, active portions of, 71 



Stem, comparison of monocotyledo- 

 nous and dicotyledonous, 70 



Stem, definition of, 40 

 Stem, dicotyledonous, minute struc- 

 ture of, 59-67* 



Stem, early history of, 64, 65* 

 Stein, functions of cells of, 71, 72 

 Stem, living parts of, 71-79* 

 Stem, modifiability of, 69 

 Stem, monocotyledonous, 57-59* 

 Stem, nature of, 40 

 Stem, structure of, 57-70* 

 Stem structure, early history of, 64, 



65* 



Stems, climbing, 47-50* 

 Stems, condensed, 54* 

 Stems, storage of food in, 78, 7'. 

 Stems, twining, 49*, 50* 

 Stemless plants, 50*, 52 

 Sterigmata, 266 

 Stiffening, mechanics for, 58*, 59, 



63*, 64* 



Stigma, 128*, 377 

 Stimulus to protoplasm, 35, 36, 39 

 Stinging hair, 418* 

 Stipa, cross section of rolled and 



unrolled leaves of, 466* 

 Stipe, 208 

 Stipules, 80, 82* 

 Stock, 69 



Stolon, with tips rooting, 436* 

 Stoma, 288, 289*, 301* 

 Stomata, 71, 103*, 118, 119 

 Stomata, operation of, 118 

 Stone fruits, uses of, 444, 445 

 Stone worts, 201, 202* 

 Storage of food in the root, 23*, 25, 



26* 



Storage of food in the seed, 8-11 

 Storage of food in the stem, 52-54*, 



78, 79 



Strawberry, 148* 

 Strobilus, 327 



Struggle for existence, 447-451, 497 

 Style, 128* 

 Suberin, 117 

 Submerged leaves, 461* 

 Successions, plant, 454-458* 

 Sucking roots, 22* 

 Sugar, 10, 11, 25, 79, 107, 112-116, 



522 

 Sugar, formed during germination. 



10, 11 

 Sugar cane, cross section of a bundle 



from, 75* 

 Sulphates, 29 

 Sulphur, 28, 29 



