GENERAL INDEX 



315 



veg., 21, 84 ; warm, 87 ; water in, 



28, 84 ; water-capacity, 86 ; water- 

 retaining capacity, 87 ; xerophytic 



factors of, 35 

 Solanum Dulcamara, incipient 



climber, 116 ; nigrum, 216 

 Solar energy, 4, 9, 65 ; spectrum, 66 

 Sonchus, latex, 216 ; arvensis, 216 

 Sorghum vulgare, 148 

 Sorrel, wood. See Oxalis 

 Sow-thistle. See Sonchus 

 Spadix, *175, 178 

 Sparganium natans, leaf, 51 

 Spathe, *175, 178 

 Species, 218, 219, 224 ; elementary, 



205, 221 ; origin of, 202 

 Spectrum, solar, 66 

 Spermaphytes, 183 

 Sphagnum, 89, 253 

 Sphagnum-bog, 231, 250, 252, 253 

 Spices, 150, 151 

 Spike, 178, *180 



Spinach (Spinacea oleracea), 150 

 Spindle-tree : aril, 196 ; honey, 172 ; 



structure of seed, 146 

 Spines : of holly, 104 ; origin of, 139 ; 



as a protection, 136, 140, *141 ; 



in xerophytes, 44 

 Spircea, pollen-fL, 169 

 Spiranthes Romanzoviana, 214 

 Spirits, 20, 151 

 Sports, horticultural, 153 

 Spurge, 216, 218 ; latex, 142 

 Stachys arvensis, 57, 216 

 Stamen, 162 

 Starch: formation of, 5, 66 ; reserve-, 



145 



Starchy seeds, 147 

 Stdlaria media, fertilization, 165 

 Stems : assimilating, 44, *45 ; edible, 



150 ; stunted growth of, 36 ; 



-tubers, 111 

 Steppes, 19, 23, 35 

 Stigma, 162 ; of wind-pollinated fls., 



167 

 Stinging hairs, *141 ; nettle, 167, 



216 

 Stipules : as bud-scales, 61 ; hollow, 



133 ; as spines, 140, *141 ; as 



tendrils, *118 

 Stitchwort, 217 ; cleistogamous fls. 



165 



Stolons, 155 

 Stomata, *f26, *27 ; in aquatics, 



49 ; regulating transpiration, 32 ; 



in xerophytes, 38, 39, 40, *41, 



*43 



Stonecrop, *39, 41, 218 ; honey, 



172 



Stones, xerophytic factors of, 35 

 Storage of food-reserves, 145 

 Stork's-bill, 217. See Erodium 

 Strand-vegetation, 277, 279 

 Stratification of plants in woods, 228 

 Strawberry : acids in, 143 ; fr., 184, 



187, *193 ; stolons of, *155 

 Strawberry-tree. See Arbutus Unedo 

 Streams, veg. of, 235 

 Struggle for existence, 203, 208, 210 

 Strychnin, 143, 148 

 Strychnos Nux-vomica, 143, 148 

 Stunted growth of stems, 36 

 Style, 162 

 Sub-alpine pastures, 230 ; rocks, veg. 



of, 290 



Subdominant plants, 227 

 Submerged leaves, 50 

 Subularia, 55 

 Succulent plants, *39, *41, *42, 58, 88 



(see Halophytes) ; fruits, 136, 192 

 Suckers, 155, 161 

 Sueda maritima, 58, 59 

 Sugar, 5, 146 ; -cane (Saccharum 



officinarum), 150, 151 ^ -maple 



(Acer saccharum), 150 

 Sumach, 212 

 Summer-annuals, 107 

 Summit-heath, 251 

 Sun, the source of energy, 4, 65 

 Sundew, 89. See Drosera 

 Sunflower : fr., 187 ; seed, 146 

 Sunlight, 4, 65 ; duration of, 10, 67 ; 



influence on veg. , 67 ; intensity of, 



67. See Light 

 Sun-plants, *72 



Survey-maps, ecological, list of, 231 

 Surveys, ecological, 229 

 Survival of the fittest, 203 

 Swamp-cypress, 212 

 Swamps : bush-, 243 ; reed-, 241. 



See Bogs and Marshes 

 Swede, 111, * 112, 150 

 Sweet chestnut, 23, 61, 136, *137, 



*187 ; cicely, 216 ; potato, 150 

 Switch-plants, 44, *45 

 Sycamore, fr., 190, *191 ; dispersal 



of fr., 195 



Symbiotic insects, 133, 144 ; pis., 132 

 Symbiosis, 132 

 Syncarpous ovaries, f!83 



Tamus communis, 214 ; berries, 149 ; 

 climbing pi., 116. See Black 

 Bryony 



