INDEX 



637 



Selaginella, Watsoniana, 384 



Wildenovii, 383 

 Selaginellales, 382, 388 

 Selection, natural, 191 

 Self -pruning, 180 

 Semi-parasitism, 341 

 Sempervivum tabulseforme, 41 



tectorum, 350 

 Senebier, Jean, 74 

 Senna, wild, 467 

 Sensitive plant, 122 

 Sepals, 435 

 Serum-therapy, 314 

 Seta, 204 

 Sex, determination of, 358 



meaning of, 360 



problem of, in plants, 344 

 Sex-organs, differentiation of, 356 

 Sexual characters, secondary, 358 

 Sexuality in molds, 353 



in Spirogyra, 355 

 Shaggy-mane mushroom, 289 

 Shelf-fungus, 303 

 Shoot, 9 



Sigillarias, 612, 613 

 SUique, 463 

 Siphonogamy, 406 

 Skein, nuclear, 186 

 Skunk cabbage, 499, 500 

 Solanacese, 480 

 Solanum, 335 



Dulcamara, 481 



integrifolium, 545 



nigrum, 545 



tuberosum, 347, 480 

 Solidago ulmifolia, 340 

 Soredia, 330 

 Sorghum halpense, 496 

 Sorus, IS4 

 Soy bean, 317 

 Spartina, 293 

 Spathyema foetida, 496 



Species, elementary, 530 



origin of, 510, 587 

 Spermatophytes, 408 

 Sphaerothica phytoptophyla, 292 

 Sphagnum, 193, 194, 200, 202, 204, 

 348 



acutifoKum, 198 



cuspidatum, 199 



cymbifolium, 195 



life-history of, 203 



squarrosum, 198 

 Sphagnales, 193 



Sphenophyllum cuneifolium, 372 

 Sphenophyllales, 618 

 Sphenopsida, 618 

 Sphenopteris Hceninghausi, 592 

 Spike, 4S9, 495 

 Spikelets, 495 



Spirogyra, 344, 345, 353, 355, 364 

 Sporangiophores, 371 

 Sporangium, iSSi iS6, iS7 

 Spore-mother-cells, 158 

 Spores, iss 



dispersal of, 164 



germination of, 165 

 Sporogonium, 201 

 Sporophylls, 156, 159 

 Sporophyte, 181, 201 



development of, 364 



evolution of, 574 

 Spruce, 140 

 StafiE-tree, 481 

 Stalk-cell, 428 

 Stamens, 417 

 Stangeria, 411 



eriopus, 598 



paradoxa, 598 

 Starch-making, 77 



steps in, 79 

 Stems, elongation of, 118 ^ 



exogenous, 65 

 Sterilization, 162 



