INDEX 



541 



Sarcina, 266, 268. 

 Sargasso sea, 260. 

 Sargassum, 260. 

 Sarracenia, 95. 

 Scale scars, 71, 74. 

 Schizocarp, 207. 

 Schizomycetes, 229, 271. 

 Schizophyceae, 271. 

 Sclerenchyma, 362, 363, 389. 

 Sclerotina fructigena, 293-295. 

 Scolopendrium, vulgare, 358. 

 Scorpioid cyme, 151, 152. 

 Scouring rush, 124, 373. 

 Screw pine, 35, 88. 

 Scutellum, 13, 14, 18. 

 "Sea mosses", 231. 

 Sea palm, 258. 

 Secale cereale, 425. 

 Seed, 6-17, 144, 156, 199, 202, 204, 

 216-223, 387, 392, 394, 405, 414, 



4i5, 4i9- 



Seed case, 419. 



Seed coats, 6, 10, n, 12, 15, 16. 



Seed, definition of, 16, 416. 



Seed, development of, 199, 203. 



Seed dispersal, 216-223. 



Seed, formation of, 202, 396, 416. 



Seed leaves, 7. 



Seed plants, 225, 230, 387-421. 



Seed, synopsis of, 416. 



Seeds, conditions of germination, 17. 



Seeds, germination of, 6-17. 



Seeds, parts of, 6-17. 



Seed structure, 6-24, 396, 415, 416. 



Selaginella, 377-380, 382, 383, 402, 

 403, 409, 417. 



Selaginella rupestris, 380. 



Selection, artificial, 499. 



Selection, natural, 489. 



Selection, severity in, 500. 



Self-pollinated flowers, 183-185. 



Sensitive fern, 359, 369. 



Sensitive plants, 86, 87. 



Sepals, 143, 152, 154, 158, 162. 



Septicidal, 208. 



Septifragal, 208. 



Sequoia sempervirens, 475. 



Sequoia washingtoniana, 475. 



Sexual reproduction, 236, 241-244, 

 247, 261, 262, 277, 281, 284, 285, 

 291. 



Sexual reproduction in powdery mil- 

 dews, 291. 



Shaddock, 442. 



Sheath, 57. 



Sheath, of leaf, 78. 



Shepherdia, 91. 



Shield coleochaete, 251. 



Shoots, winter condition of, 70-76. 



Sieve tubes, 64. 



Sigillaria, 384, 385. 



Silene, 189. 



Silicic, 209. 



Silicon, 124. 



Silique, 209. 



Silk grass, 435. 



Silphium laciniatum, 85. 



Simple leaves, 80. 



Siphon green algae, 246. 



Siphonales, 251. 



Siphoneae, 228, 246. 



Sisal, 435. 



Smilacina racemosa, 149. 



Smilax, 52. 



Smut, prevention of, 308. 



Smuts, 305-308. 



Smyrna fig, 195-197. 



Solanaceae, 446. 



Solanum tuberosum, 446. 



Solidago, 449. 



Soredia, 299. 



Sorghum, 428, 429. 



Sorghum vulgare, 429. 



Sorus, 312, 359, 360. 



Sourwood tree, 445. 



Spadix, 150, 153, 178. 



Spartium, 193. 



Spathe, 150, 178, 180. 



Specialized stems, 45,48. 



Species, 226. 



Sperm case, 242, 244, 247, 260, 262, 



281, 335, 338, 347, 365, 366, 391, 



409. 



Sperm cell, 400, 402. 

 Sperm nucleus, 199-202, 285, 395. 

 Sperm nucleus, male nucleus, 199- 



202. 

 Spermatophyta, 204, 225, 230, 387- 



421. 



Spermatophytes, 225. 

 Spermogonium (a), 311, 316, 319, 



320. 

 Sperms, 242, 244, 245, 247, 252, 260, 



262, 281, 338, 366, 372, 375, 378, 



380, 401, 419. 

 Sphaerella lacustris, 240. 

 Sphaeriales, 291. 

 Spha^ro-crystals, 24, 35. 



