490 



INDEX 



jrcus alba, 208. 

 icrcus coccinea, 208. 



jrcus rubra, 208. 

 lillworts, 350. 

 Hiinine, 407, 418. 



Races of plants, 464, 465. 



Radicle, 2, 5, 7-11. 



Ramie, 405. 



Ranunculus acris, 142, 143, 187. 



Raphe, i, 184. 



Raspberries, 42, 192-195, 202, 406. 



Rattan, 40. 



Ray flowers, 156. 



Records, in plant breeding, 478. 



Red algae, 239-242; uses, 243. 



Red bud, 410. 



Red rust of wheat, 282. 



Red snow plant, 220. 



Reindeer moss, 271, 272. 



Reinforced fruits, 188, 195. 



Respiration, 85, 90, 108-116. 



Respiration, conditions of, 112. 



Rhabdonia, 242, 324. 



Rhizobium leguminosarum, 121. 



Rhizoids, 249, 250, 305, 306, 321, 



335- 



Rhizome, 41, 333. 

 Rhizopus nigricans, 248-251. 

 Rhodochytrium, 211. 

 Rhododendron catawbiense, 415. 

 Rhododendron maximum, 415. 

 Rhododendrons, 93, 94, 140, 415. 

 Rhodophyceae, 209, 239. 

 Rhus hirta, 67. 

 Rhus typhina, 67. 

 Riccia, 304, 311, 315. 

 Rice, 396. 

 Richardia, 165. 

 Rings, annual, 53, 59, 60. 

 Robinia, 410. 

 Roccella tinctoria, 275. 

 Rock weed, 236, 237. 

 Root absorption in desert, 449. 

 Root cap, 30, 32. 

 Root climbers, 40. 

 Root hairs, 30-36. 

 Root pressure, 95. 

 Root sheath, 8, 9, 13. 

 Root stocks, 41, 42, 330. 

 Root systems, 26^-28. 

 Root tubercles,^ 1-123. 

 Root tubers, 29, 45. 

 .Roots, 1-12, 26-32. 



Roots, growth of, 20-25; motor 

 zone, 21, 22; perspective zone, 21, 



22. 



Rosaceae, 406. 



Rose family, 406. 



Rose leaf, 74. 



Rosette plants, 450. 



Rosettes, 81. 



Royal fern, 340. 



Rubber plant leaf, 72. 



Rubiaceae, 418. 



Rubiales, 418. 



Rust fungi, 279-290; losses from, 



279. 



Rutaceae, 411. 

 Rye, 395- 



Sac fungi, 261-275. 



Sac fungi, life history of, 275. 



Saccharomyces ceriviseae, 114, 115, 



268. 



Saccharum omcinarum, 398. 

 Sago, 401. 

 Sago palm, 401. 

 Salicales, 403. 

 Salsify, 419. 

 Saltpeter, 119. 

 Samara, 189. 

 Sand dunes, 452. 

 Sap wood, 59. 

 Saprolegnia, 254-256. 

 Saprophytes, 129-139, 246. 

 Saprophytes, nutrition of, 130. 

 Saprophytic fungi, 136, 248. 

 Sarcina, 135, 245. 

 Sargasso sea, 238. 

 Sargassum, 238. 

 Scale leaves, 87, 89. 

 Schizocarp, 189. 

 Schizomycetes, 209, 245. 

 Schizophyceae, 245. 

 Sclerenchyma, 332. 

 Sclerotinia fructigena, 267, 268. 

 Scolopendrium vulgare, 328. 

 Scouring rush, 343. 

 Screw pine, 30, 81. 

 Scutellum, 9, 13. 

 Seaweeds at low tide, 454. 

 Secale cereale, 395. 

 Seed, 1-20. 



Seed case, of angiosperms, 378. 

 Seed coats, 1-12. 

 Seed, development of, 182. 

 Seed, formation of, 185. 



