312 



BRITISH PLANTS 



Ants and flowers, 172 ; symbiosis, 

 133 



Apocarpous ovaries, tl83 



Apple, 149 ; bud-scales, 61 ; poUi- 

 nation, 174; fr., 143, 184, 193, 

 194 ; suckers, 155 



Apricot suckers, 155 



Aquatic associations : in slowly- 

 flowing water, 235 ; standing 

 water, 236 ; swiftly-flowing water, 

 234 



Aquatics, t28 ; aeration of, 52 ; air- 

 spaces in, 47 ; annual, 55 j brood- 

 buds in, 54 ; ciiars. of, 47 ; 

 chlorophyll in, 49 ; colour of, 53 ; 

 cuticle in, 48 ; dangers to which 

 exposed, 52 ; distribution, 233 ; 

 free-floating, 237 ; leaf-form in, 

 50 ; in relation to light, 52 ; 

 origin of, 55 ; pollination, 166, 

 275 ; propagation, 53 ; respiration 

 in, 48, 50, 52 ; rooted, 237 ; roots, 

 49 ; seeding of, 54, 275 ; trans- 

 piration of, 52 ; vascular system 

 of, 49 ; zoning of, 236 



Aquatic vegetation : fresh - water, 

 230, 231, 233 ; maritime, 231, 275 



Aqueous rocks, t82 



Arabis, 115 



Arable land, 18, 19 



Arbutus Unedo, 23, 211, 212, 213 ; 

 berries, 149 



Arctic plants, 72 



Arenaria ciliata, 213 ; pevloides, 

 218 



Aril, 196, 197 



Aristolochia (Birthwort or Dutch- 

 man's-pipe), fly-trap, 176 



Arrack, 151 



Arrowhead. See Sagittaria sagitti- 

 folia 



Arrowroot, 150 



Artichoke, 150 



Artificial habitats, 16, 215, 216 ; 

 manures, 97 ; pastures, 20, 261, 

 264 



Arum maculatum berries, 149; poUi- 

 uation, *175 



Ash, 22, 269 ; bud-scales, 61 ; fr., 

 186, *187; fruit-dispersal, 195; 

 weeping, origin of, 154 



Ash of plants, 80 



Ash-oakwood association, 229, 272 



Ashwood-association, 229, 272 



Asparagus, 150 



Aspidistra: leaf -type, 42: pollina- 

 tion. 176 



Assimilation, 4 ; in aquatics, 63 ; 

 light-rays necessary for, 66 ; of 

 nitrogen by bacteria, 95, 99 ; in 

 xerophytes, 38 



Associations, 224, 227 ; alpine, 251, 

 255, 259 ; aquatic, 234 ; bog-, 246, 

 251, 252, 253 ; classification of, 



229 ; grassland-, 257 ; herbaceous, 



230 ; influence of man on, 226 ; 

 maritime, 275 ; marshland-, 241, 

 244 ; methods of studying, 226 ; 

 moorland-, 225, 248 ; strand-, 277 ; 

 woodland-, 265 



Atmosphere, 6, 34, 76 

 Atmospheric equilibrium, 77 

 A triplex portvlacoides, 218 

 Atropa Belladonna : poison, 136, 143; 



pollination, 174 

 Atropin, 143 

 Aucuia, 154 

 Autogamy, tl64 

 Autotrophic pis., 6, 123 

 Avens See Oeum; mountain-. See 



Dryas octopetala 

 Awl-type of leaf in aquatics, 50 

 Awlwort. See Suhularia 



Bacteria : action on dead organic 

 matter, 83 ; injurious, 61 ; nitrate, 

 95 ; nitrogen-, 95, 99 ; parasitic, 

 125 ; saprophytic, 123 ; soil-, 83, 

 93, 95, 96, 97, 123 



Ballota nigra, 216. See Horehound 



Balsam. See Impatiens Ndi-me- 

 tangere 



Bamboo, 212 



Banana, 149. See Musa Sapientum 



Barberry : honey, 172 ; root-suckers, 

 155; spines, 140, *141. See 

 Berheris vulgaris 



Barley : alcohol from, 151 ; crops, 98 ; 

 cultivation of, 20 ; food, 147 ; 

 starch, 146 



Bartsia : parasitic nature of, 126 ; 

 water-glands of, 127 



Bastard - toadflax. See Thesium 

 humifusum 



Bay-laurel, 42 



Beach, 16, 58 ; veg. of pebbly beach, 

 283 ; of sandy beach, 279 



Beachy Head, 77, 284 



Bean : climber, 116 ; protein of, 147 ; 

 root-nodules, 95 ; seed, 146 ; dis- 

 persal of seed, 195 



Bedstraw, 217. See Galium 



Beech, 22 ; bud-scales, 61 ; fr., 

 187 ; insects on leaves of, 144 j 



