542 



PRACTICAL BOTANY 



Raceme, 515* 



Radial symmetry, 108, 109* 



Rafflesia, 384 



Rainfall, 437 



Rainfall map of United States, 511* 



Ray, medullary, 50* 



Ray flowers, 369* 



Receptacle, 105 



Red algse, 209 



Red clover, leaf of, 64* 



Redwood, 313*, 512 



Regions of vegetation in United 



States, *503-513 

 Reindeer moss, 239 

 Reproduction, 160, 194 

 Reproduction, sexual, in flowering 



plants, 21*, 22*, *1 15-1 18 

 Reproduction by leaves, 89 

 Reproduction by portions of stem, 



82, *83-89 

 Resin duct, 303* 

 Respiration, 19, 76 

 Response, 389 

 Resting buds, 90* 

 Rhizoids, 214, 215* 

 Rhizopus, *214-217 

 Rhododendron, 69* 

 Rhodophycese, *209-212 

 Riccia, 266, 267 

 Ricciocarpus, 266* 

 Rice, 339, 340*, 455, 458 

 Ring, annual, 50*, 51 

 Ring-porous wood, 391* 

 Rise of water in stems, 11, 80 

 Rockweeds, 207* 



Rocky Mountain region, *506-508 

 Root, *5-10, *24-38 

 Root, dicotyledonous, section of, 24-* 

 Root, fleshy, 34* 

 Root absorption, 7-9 

 Root climbers, 61, 63* 

 Root hair, 7, 8*, 9 

 Root pressure, 9 

 Root rot, 234 



Root system, 6*, .7*, 26, 27 

 Root tubercle bacteria, 374-378, 449 

 Root-tubercles, 36, 37 

 Roots, aerial, 30, 31* 

 Roots, air requirements of, 29 

 Roots, anchorage by, 5, 6*, 25 ' 

 Roots, earth, 25, 26 

 Roots, effects of, on soil, 28 

 Roots, parasitic, 35, 36 

 Roots, pull of, 27 

 Roots, reproduction by, 33* 



Roots, storage of food and water in, 



33, 34, 35 



Roots, structure of, 24*, 49* 

 Roots, water, 30 

 Roots, water-lifting by, 9 

 Rootstock, 72*, 73*, 275*, 276, 277 

 Roquefort cheese, 231 

 Rose family, 352*, 353 

 Rose family, fruits of, 459-462 

 Rose mildew, 234 

 Rosette plants, 57*, 58 

 Rosin, 316 

 Russian thistle, 148 

 Rusts, 240 

 Rye, 455, 457 



Sac fungi, *226~234 



Saccharomycetes, 232*, 233 



Sagebrush, 508* 



Sago palm, 317 



Salt marsh plants. See Halophytes 



Salts, 498, 499 



Saltwort, 499 



Salvinia, 291* 



Sap, movements of, 9, 11, 80 



Saprolegnia, 217*, 218* 



Saprophytes, 213, 218, 372, 381*, 



382* 



Saprophytic bacteria, 374 

 Saprophytism, 372 

 Sapwood, 51 

 Sargasso seas, 207 

 Sargassum, 207 

 Sassafras wood, section, 391* 

 Scaly buds, *90-96 

 Schizomycetes, 161, 179 

 Scion, 88* 

 Sclerenchyma, 303* 

 Sclerotinia, *226-228 

 Scouring rush, 291*, 293 

 Scramblers, 61 

 Scutellum, 139* 

 Sea lettuce, 204 

 Seed, 21-23, *136-141, 309 

 Seed, definition of, 22, 23, 147, 148 

 Seed coats, 138, 139 , 

 Seed distribution, *146~155 

 Seed leaf, 136*, 137* 

 Seed plants, *5-155, 299, 321 

 Seedlings, 22*, 23*, 137*, *141-145 

 Seedlings, mutilated, growth of, 144* 

 Seedlings, types of, *141-143 

 Selaginella, 293-295 

 Selection by plant breeder, 412, 415, 



416, 421-425, 432 



