364 INDEX 
Spermatophytes, 208. Stipule, 6. 
Spike, 232. Stock, 56, 317. 
Spirogyra, 113. Stoma, 16. 
Spongy tissue, 18. 
Sporangium, Angiosperm, 224; 
brown Algz, 121; conifer, 212; 
Equisetum, 199; fern, 191; 
Mucor, 141; red Alge, 126; 
Selaginella, 203. 
Spore, 106; Angiosperm, 22+, 235; 
brown Algze, 121; Equisetum, 
199; green Alge, 106; mildew, 
145; Gedogonium, 108; red Algze, 
126; rusts, 149, 151; swimming, 
106; Vaucheria, 112. 
Spore-case, moss, 180. 
Spore-fruit, mildew, 
Algee, 126. 
Sporophyll, 207; Equisetum, 199. 
Sporophyte, 171; Anthoceros, 173; 
conifer, 215; club-moss, 202; 
fern, 187, 195; Jungermannia, 
173; leafy, 207; Lycopodium, 
202; Marchantia, 170; moss, 
179. 
Spring flowers, 67. 
Spur, 223. 
Squash, 315. 
Stamen, 224; Angiosperm, 221; 
conifer, 212. 
Standard, 291. 
Starch, 21. 
Stem, 41; annual, 53; climbing, 
47; direction, 42; erect, 42; ex- 
ternal structure, 41; growth, 59; 
internal structure, 50; perennial, 
53; prostrate, 45; special forms, 
59. 
Steppes, 344. 
Stigma, 227. 
Stimulus, 90. 
Stipe, 155. 
146; red 
Stone-fruit, 239, 288. 
Strawberry, 286. 
Strobilus, club-moss, 202; conifer, 
212; Equisetum, 198; Lycopo- 
dium, 202; Selaginella, 203. 
Style, 227. 
Subsoil, 78. 
Subtropical desert, 341. 
Sucker, 70. 
Sugar-cane, 270. 
Summer spore, 149. 
Sundew, 38. 
Swamp, 331; forest, 336; thicket, 
332. 
Sweet potato, 313. 
swimming spore, 106. 
Sympetale, 223, 282, 302. 
Tangerine, 299. 
Tap-root, 72. 
Tea, 300. 
Temperature, plant associations, 
325. 
Tendril, 35, 48, 60. 
Testa, 85, 218, 237. 
Tetraspore, 126. 
Thallophytes, 165, 183, 208. 
Thicket, mesophytic, 348; xero- 
phytic, 344. 
Thorn, 35, 62. 
Timber, conifer, 218; hardwood, 
284. 
Toadstool, 153. 
Tobacco, 306. 
Tomato, 306. 
Tracheary vessels, 52; annular, 52; 
dotted, 53; pitted, 53; spiral, 
52. 
Transpiration, 22. 
