Ind 



ex 



Nitrogen, 43 

 Nostoc, 42 

 N-rays, 217 



Oak forests, 223, 225, 229, 231, 250 



Oak-leaves, 182 



Oats, 284, 285 



Oenothera Lamarckiana, 298 



Old man's beard lichen, 66 



Open floras, 21, 90, 93, 198 



Ophrys, 122 



Opsonins, 57 



Oranges, 287 



Orchids, 120, 15 1, 277 



Oscillatoria, 32 



Pacific Islands, 280 

 Palm-leaves, 332 

 Pampas, 136, 266, 267 

 Papyrus, 134 

 Parasites, 41, 147 

 Paspalum, 135 

 Patanas of Ceylon, 185 

 Peas, Mendel on, 301 

 Peat, peat-moss, 70~7*> 199. 225-227 

 Perfume industry, 312 

 Perie bush, 79 

 Permanent pasture, 269-273 

 Petals, 109 

 Petroleum, 82 

 Phagocytes, 56 

 Phalaris, 137 

 Phosphorescence, 38, 59 

 Phragmites, 127, 130, 231 

 Physcia, 67 

 Pine, structure of, 237 

 Pinus maritimus, 167 

 Pitcher plant, 1 50 

 Plankton, 36 



Plant breeding, practical, 284-294 

 „ ,, theory of, 295-306 

 Podostemaceae, 183 

 Poisonous plants, 199, 269, 310 

 Poisons, effect of, 150, 160, 329, 330 

 Pollen parent, effect of, 305 

 Pollination, 116-118, 151, 159 

 Polygonum amphibium, 127 

 Polypodium, 80, 208 

 Polytrichum, 70 

 Pond weed association, 130 

 Potatoes, 286, 293 

 Potentillas, change in, 185 

 Prairies, 267 

 Preglacial plants, 218, 227, 228 



Protoplasm, 17, 123, 140-143, 147 



149, 338 

 Psamma, 165-168 

 Pyrocystis, 38 



Radium, 216 

 Kafflesia, 203 

 Rain, absorption of, 193 

 Rain-leaves, 188 

 Ray-florets, 121, 188 

 Reconquest of water, 125 

 Reed association, 130, [63 

 Reid, Clement, 225, 227 

 Regeneration, 1 5 5 

 Renanthera Lowii, 1 14 

 Renwick, Mr., 218, 219 

 Resin, 154. 1 55. 33^ 

 Respiration, 331 

 Retama, 171 

 Rhythm, 216 

 Rice, 262 



Rock lichens, 65-69 

 Roman Britain, 229 

 Rontgen rays, 216 

 Roots, 148 

 Rubber, 320 

 Rush association, 132 

 Russell, Dr., 216 

 Rust fungi, 82 



Sagina, 186 



Sago, 274, 275 



Salix, 93 



Salt, 157-162, 329 



Saltwort, 1 58-161 



Sand-dunes, 164-167 



Sand plants, 164 



Saprophytes, 335 



Sargasso Sea, 36 



Scent, 113 



Scented Labiates, 308, 310 



Scirpus associations, 130, 163 



Scotch pine, forests of, 75, 223, 225- 



230, 238, 239 

 Scrub, 307-315 

 Seaside plants, 157-168 

 Season of flowering, 119 

 Seed, dispersal of, 102, 129, 202, 203, 



277 

 Selection, method of, 284 



,, by one seed, 287 



Self-surgery, 153, 154, 332 

 Sempervivum, 173 

 Sense life and sensitiveness, 1 23, 1 40- 1 5 1 



351 



