462 



INDEX 



rootstock, iss 

 Rosacea, 332 

 rose cold, 306 

 rose family, 292, 332 

 roses, 270, 277 

 rosette, 140, 212 

 rosin weed, 250 

 rotation of crops, 15, 392 

 rubber, 3, 53, 194 

 Rudbeckia, 62, 302 

 runners, 126 

 Russian thistle, 327 



salts, 349 



Salvia, 313, 314 



samara, 331, 332 



sand, 99 



sanitation, 375 



sap, 75, los 



saprophyte, 373 



sapwood, 177 



Sarracenia, 253 



scalding of leaves, 222 



scales, 299 



scaly buds, 188 



scattered arrangement, 83, 165, 171 



et seq. 

 scientific method, 20, 22 

 scion, 181, 182 

 scouring rush, 422 

 screw pine, 134 

 Scrophularia, 319 

 seaweeds, 362,. 372, 373 

 secondary growth, 1 29 

 secondary roots, 125, 126 

 seed, 32s el seq., 39S, 435, 438 

 seed coat, 353 



seed dispersal, 63, 327, 353 el seq. 

 seed habit, 267 

 seedless fruits, 335 

 seedling, 66, 157, 341, 342, 353 

 seed plants, 38 et seq., 431 el seq. 

 seeds, vitality of, 339 

 seed testing, 340 

 seed vessel, 273 

 Selaginella, 425 et seq. 

 self-planting fruits, 334 

 self-pollination, 263 

 sensitive plant, 247 

 . 59, 271 



serrate leaves, 207 



sessile, 209, 299 



seta, 400, 401, 406 



sex organs, 267 



sex process, 268 



sex reproduction, 57, 367 



shepherd's purse, 140, 297 



shoot, 86, ISS 



shrubs, 146 



sieve vessels, 17s, 176 



silk of corn, 283 



siphonogamy, 436 



skunk cabbage, 312 



slip, S7 



smilax, IS4 



snails, 303 



snapdragon, 294, 314 



sodium, 349 



soil, 6, 98 et seq., 376, 378, 391 et seq. 



soil bacteria, 376 



Solomon's seal, 156, 205 



solute, 90 



solution, 89 



solvent, 90 



sori, 417, 418 



sorrel, 248 



soy beans, 378 



spadix, 279 



Spanish bayonet, 314 



spathe, 279 



spawn, 381 



species, 44, 305, 446 



sperm, 275, 367, 398, 399, 400, 402, 



408, 409, 420, 429 

 spermatophytes, 183, 361, 431 el seq., 



440 

 spike, 281, 299 

 spikenard, 217 

 spiral vessels, 174 

 Spirogyra, 370, 371 

 spongy mesophyll, 85, 239 

 spongy parenchyma, 164 

 sporangia, 417, 418, 420 

 spore, 268, 326, 35S, 365, 366, 387, 394, 



409, 420 



spore print, 380, 381 



sporogonium, 400, 401, 402, 403, 406, 



409, 417 

 sporophore, 379, 380, 381, 384 

 sporophyll, 422, 423, 424 

 sporophyte, 402, 403, 408, 420 

 spring beauty, 161 



