INDEX 



637 



Segregation, law of, 555 



Mendelian, 554, 556 

 Selaginella, 382, 384, 431 



amoena, 383 



Kraussiana, 387 



life-cycle of, 388 



Martensii, 385 



Watsoniana, 384 



Wildenovii, 383 

 Selaginellales, 382, 388 

 Selection, natural, 191 

 Selfing, 560 

 Self-pruning, 180 

 Semi-parasitism, 341 

 Sempervivum tabulaeforme, 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 

 Silique, 463 

 Siphonogamy, 406 

 Skein, nuclear, 186 

 Skunk cabbage, 499, 500 

 Solanaceae, 480 

 Solanum, 335 



Dulcamara, 481 



integrifolium, 545 



nigrum, 545 



Solanum tuberosum, 347, 480 

 Solidago ulmifolia, 340 

 Soredia, 330 

 Sorghum halpense, 496 

 Sorus, 154 

 Soy bean, 317 

 Spartina, 293 

 Spathyema fcetida, 496 

 Species, elementary, 530 



origin of, 510, 587 

 Spermatophytes, 408 

 Sphaerothica phytoptophyla, 292 

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

 348 



acutifolium, 198 



cuspidatum, 199 



cymbifoliuni; 195 



life-history of, 203 



squarrosum, 198 

 Sphagnales, 193 



Sphenophyllum cuneifolium, 372 

 Sphenophyllales, 618 

 Sphenopsida, 618 

 Sphenopteris Hoeninghausi, 592 

 Spike, 459, 495 

 Spikelets, 495 



Spirogyra, 344, 345, 353, 355, 364 

 Sporangiophores, 371 

 Sporangium, 155, 156, 157 

 Spore-mother-cells, 158 

 Spores, 155 



dispersal of, 164 



germination of, 165 



swarm-, 251 

 Sporogonium, 201 

 Sporophylls, 156, 159 

 Sporophyte, 181, 201 



development of, 364 



evolution of, 574 

 Spruce, 140 

 Staff-tree, 481 

 Stalk-cell, 428 



