INDEX 
Prostrate, 95. 
Protection, 199, 204, 207, 280, 287. 
Proteins, 3, 8, 33, 188, 204. 
Prothallium, 407. 
Protonema, 396. 
Protoplasm, 6, 7, 57, 58, 67, 110, 116. 
Pteridophytes, 335, 411, 412. 
Puccinia, 360. 
Pure dominant, 258, 259. 
Pure forest, 139, 324. 
Pure recessive, 258, 259. 
Pyenidia, 363. 
Quartered cut, 135. 
Raceme, 161. 
Rhachis, 178. 
Radial section, 132, 135. 
Radicle, 46. 
Rhaphe, 13. 
Ray, 161, 391. 
Ray flowers, 231. 
Receptacle, 211, 288, 289, 388, 390, 398. 
Recessive, 257, 258. 
Red rust, 359. 
Regular flower, 219. 
Reproduction, 338, 351, 358, 383. 
Respiration, 30, 31, 191, 192. 
Resting spore, 338, 342, 358, 394. 
Reticulation, 172, 402. 
Retrogressive evolution, 418. 
Revolute, 373, 404. 
Rhizoids, 379, 386. 
Rhizome, 105. 
Ringing, 127. 
Rings of growth, 122, 123, 134, 135. 
Rogue, 260. 
Root cap, 39. 
Root hairs, 38, 67. 
Root pressure, Exp. 49. 
Root pull, 69. 
Rootstock, 105. 
Root system, 89.. 
Root tubercles, 63, 309. 
Rosette, 197. 
Rotation of crops, 24, 327. 
Runner, 95. 
Samara, 296. 
Sap movement, 125, 126, 128, 129. 
Saprophyte, 86. 
Sapwood, 131. 
Szale leaves, 101, 106, 107, 147-149, 207. 
Scape, 107, 159. 
Scorpioid inflorescence, 162; Figs. 173- 
176. 
Screenings, 20; p. 28, Qn. 22. 
Secondary roots, 87, 42, 79. 
Seed, 11-18, 332, 415, 
373 
Seed coat, 12, 14, 15, 43, 
Seedless fruits, 285, 286. 
Seedlings, 36, 42, 43, 45. 
Seed plants, 331, 414. 
Seed vessel, 282. 
Selection, 260, 265, 286. 
artificial, 262. 
natural, 261. 
Self-fertilization, 254, 271. 
Sepals, 211. 
Sessile, 167, 214. 
Seta, 399. 
Sexual generation, 395, 396, 406, 410, 416. 
Sexual reproduction, 394, 395, 410. 
Sheath, 67, 116. 
Shrinking of timber, 136. 
Sieve tube, 114. 
Slabs, 134. 
Sleep movements, 200. 
Soils, 75, 77. 
Sori, 404. 
Spathe, 221. 
Specialization, 237. 
Spermatophytes, 331, 335, 394, 414. 
Spermatozoid, 389. 
Spermogonia, 363. 
Spike, 161. 
Spirillum, 348. 
Spirogyra, 341. 
Sporangia, 390, 405. 
Spore, 332, 349, 350. 377, 406, 410. 
Spore case, 390, 393, 405. 
Spore print, 376. 
Sporidium, 361. 
Sporogonium, 393, 399. 
Sporophyll, 406, 414. 
Sporophyte, 393-395, 399, 406, 410, 412, 
414, 416. 
Sport, 264. 
‘| Stamen, 212, 213. 
Staminate, 267, 268. 
Staminodia, 244. 
Standard, 238. 
Starch, 3, 4, 187, 204, 288; Exps. 69, 70 
Stems, 90-99. 
Sterile flower, 267. 
Sterilization, 354. 
Stigma, 214. 
Stigmatic surface, 223. 
Stimulus, 98, 186, 201. 
Stipe, 240, 372, 402. 
Stipule, 149, 165, 166. 
Stolon, 95. 
Stoma, 181, 182, 183. 
Stomata, 181, 182. 
Stone fruit, 292. 
Storage of food, 2, 3, 4, 17, 70, 103, 19!- 
107, 287. 
Strangling fig, 88. 
