Index 



335 



Preservation of foods, 257. 



Pressure, of growth, 184; osmotic, 174; 



root, 177. 



Prickly lettuce, 40 ; pear, 58. 

 Proteins, making of, 32; use of, 32, 33. 

 Prothallus, 288. 

 Protococcus, 235. 

 Protonema, 279. 

 Protoplasm, 151. 

 Puffballs, 267. 

 Pulvinus, 45. 



Raceme, 198. 



Rainfall, distribution of, 51, 144; effect 

 on yield of corn, 48, 51. 



Raspberry, 213, 217. 



Rattan, 125, 163. 



Receptacle, 200. 



Red-bud tree, 44. 



Red pigment, 65. 



Reproduction, 10, 197, 206; and agri- 

 culture, 217; asexual, 243; by seeds, 

 207, 300; sexual, 205, 243. 



Reproductive phase of plant life, 197. 



Reservoirs, cleaning, 246. 



Respiration, 82; and shipping, 84; con- 

 trasted with photosynthesis, 83; in 

 roots, 82, 179; rate of, 84. 



Response, 131 ; to aerial environment, 

 2 755 to gravity, 130, 149, 182; to light, 

 131, 149, 183 ; to water, 131, 157, 183. 



Rhizoids, 273, 276 ; moss, 278. 



Rhododendrons, 194. 



Rhubarb, 195, 198. 



Rice, 77, 145, 307, 308. 



Root, contraction, 185; hairs, 168; pres- 

 sure, 177; processes, 166. 



Roots, and bacteria, 194, 258; and fungi, 

 194; and transplanting, 190; classifica- 

 tion of, 1 66; commercial uses of, 194; 

 distribution of, 183 ; of climbers, 182, 

 187; of conifers, 296; of ferns, 285; of 

 hydrophytes, 187 ; of mesophytes, 187 ; 

 response to gravity, 182; response to 

 light, 183 ; tissues of, 169. 



Rootstock, 159, 219; calamus, 122. 



Rose family, 312. 



Rosin, 161, 162. 



Rubber, 163, 215. 



Running cypress, 287. 



Rushes, 157. 



Russula, 267. 



Rusts, 263. 



Salsify, 194. 

 Sand-reed grass, 159. 

 Sanitation, 252. 



Saprophytes, 249. 



Sapwood, 130. 



Sassafras, 195. 



Scale leaves, 160, 161. 



Science, defined, 3. 



Seaweeds, 246. 



Sedges, 38, 157. 



Seeds, 198, 205, 207 ; economic impor- 

 tance of, 214; of conifers, 198, 211. 



Selaginella, 59. 



Selection, 220, 228; natural, 327. 



Self-pruning, 69. 



Sensitive plant, 44. 



Sepal, 200. 



Sequoia, 98, 154, 229. 



Shasta daisy, 222. 



Shrubs, 94. 



Sieve tubes, 122. 



Silviculture, 100. 



Simple plants, summary of, 270. 



Sirup, 163. 



Sisal, 90, 91. 



Smilax, 107. 



Smuts, 266. 



Snapdragon, 198. 



Soil, 141 ; bacteria, 257 ; cultivafton of, 

 143 ; elements, 141 ; erosion, 186, 187 ; 

 temperature, 146. 



Solomon's seal, 98, 159, 185. 



Sorghum, 163. 



Soy bean, 33, 78, 194. 



Sperms, 205. 



Spike, 198. 



Spirogyra, 236. 



Spores, asexual, 241 ; resting, 238; sexual, 

 241 ; swimming, 238. 



Sports, 225; bud, 226. 



Spruce, 114. 



Stamen, 200. 



Starch, 28, 74, 77. 



Stem, processes, 118; structure, 118, 119, 



!54- 



Stems, advantages of horizontal, 104; as 

 photosynthetic organs, 106 ; commercial 

 products from, 161 ; excurrent and deli- 

 quescent, 1 1 1 ; external features of, 102 ; 

 growth of, 128 ; in relation to light, 131 ; 

 of climbing plants, 155 ; of hydrophytes, 

 156; of xerophytes, 157 ; underground, 

 97, 130; upright, 102. 



Stigma, 200. 



Stipules, 14. 



Stock, 132. 



Stomata, 19, 115. 



Storage, food, 74, 77, 105, 125, 159, 160, 

 161 ; water, 58, 106, 158, 189. 



Strawberry, 10. 



