316 



BRITISH PLANTS 



Tannin, 150 



Tapioca, 150 



Taraxacum. See Dandelion 



Tares, 218 



Taxodium, 212 



Tea, 151 



Telluric water, f28, 85, 86 



Temperature, 6, 10, 11, 18 ; effect on 

 pis., 74, rocks, 81, soil, 87 ; effect 

 on transpiration, 34, 74. See 

 Heat and Cold 



Tendril-climbers, 117 



Tendrils: leaf-, 118; leaf-tip, 119; 

 morphology of, 118 ; petiole-, 

 119; stipule-, 119; stem- or 

 shoot-, 118 



Terrestrial plants, 28, 114 



Thalictrum minus, pollination, 167 



Thesium humifusum, parasitic 

 nature of, 126 



Thickets, 268 ; alder- and willow-, 

 229, 243, 269 ; hazel-, 269 



Thistle, 198; fr., *195 ; prickles, 

 141 



Thorny plants, 17, 44, 139 



Thorns : origin of, 139 ; as a protec- 

 tion, 140 ; in xerophytes, 17, 44 



Thrift, infl., 181 



Thrum-eyed fls. of primrose, 177 



Tiger-lily, bulbils, 160 



Till, 80 



Timber, 22, 152 



Toadflax (Linaria), 62, honey, 170, 

 pollination, 173 ; bastard- (see 

 Thesium) 



Tobacco, 152 ; -plant : fl., 174, honey, 

 173, pollination, 173 



Toddy, 151 



Toothwort, 126, 217. See Lathroea 



Touch-me-not, 217. See Impatiens 

 Noli-me-tangere 



Tragapogon, latex, 142 



Transpiration, 26, 32 ; in aquatics, 

 52 ; causes which increase, 34, 35 ; 

 regulated by stomata, 32 ; in- 

 fluenced by wind, 76 ; in winter, 

 60 ; in xerophytes, 32, 34, 35, 36, 

 40 



Transpiration-current, 25, 32 ; in 

 hygrophytes, 29 ; in xerophytes, 

 32 



Traveller's-joy, 214. See Clematis 

 Vitalba 



Treacle-mustard, 216 



Tree-growth : limit of, in England, 

 270 ; effect of wind on, 77 ; effect 

 of xerophytic conditions on, 36 



Trees, deciduous, 60, 109 

 Trichomanes radicans. See Killar- 



ney fern 

 Trifolium arvense, 60 ; repens (white 



clover), 171, 174 

 Trimorphie flowers, 177 

 Tropceolum majus : hydathodes, 28 ; 



tendrils, 119 ; fr. and seed, *147 

 Tropical rain-forests, 9, 16, 23, 27, 



121 

 Tropics: climate, 10; duration of 



sunlight, 67 ; veg., 10, 23 

 Tropisms, 68 

 Tropophytes, 30, 31, 57 ; hygro- 



philous, 58 ; mesophilous, 58 ; 



xerophilous, 58 

 Tuberous roots, 111 

 Tubers, 60, 62, 110 ; food-reserves in, 



150 ; multiplication by, 159, 161 ; 



root-, 111 ; stem-, 111 

 Tufted habit, 115 

 Tulip, 62, 63 ; bulb, 156, *157 

 Tulip-tree, 212 

 Tundras, 21 

 Turgidity, 24 

 Turnip, 108, 111, 150 

 Turpentine, 142 

 Twiners, 116 

 Typha, 62 



Ulex europceus (see Gorse) ; minor, 

 214 



Ultra-violet rays, 65 



Umbel, 178, 181, *182 



Umbelliferae : fls., 176 ; fr., 186, 191, 

 *192 ; honey, 172 ; infl., 181 ; 

 .insect- visitors, 170 ; nectaries, 

 169, *170 ; seed, 146 



Uncultivated land, 18 



Underground perennating organs, 

 109 ' 



Undergrowth of woods, 266 



Units of classification. See Variety, 

 Species, Genus, Association, For- 

 mation 



Urtica : stinging hairs, *141 ; dioica, 

 216 ; urens, 216 



Utricularia : brood- buds, 54 ; in- 

 sectivorous habit, 131, *132 ; 

 leaf-form, 50 ; pollination, 56 ; 

 absence of roots, 49 



Valerian, 152; infl., 180; pollina- 

 tion, 170 



Vaccinium-moor, 231, 249, 251, 255 

 Vallisneria, 50 

 Variation, 210, 219, 220 ; bud-, 153 



