Index 



357 



Perfect flowers (see " Am- 

 phisporangiate ") 



Perfume in flowers, 177, 228 



Persimmon, 269, 279 



Petunia, 229 



Phaeophycese (see also 

 "Brown Algae"), 58, 63 



Phalloidese, 225 



Phanerogams (see " Seed- 

 plants") 



Photosynthesis, 5, 13, 29, 30, 

 34, 55, 56, 67, 94, 188, 203, 

 205 



Phyllodia, 200, 207 



Phycomycetes (see " Alga- 

 fungi") 



Physiological factors in he- 

 redity, 22 



Pine, 123, *I24, 125, 126, 244, 

 246, 252, 269, 292 



Pineapple, Pineapple family, 



20, 247, 269 



Pinguicula (see " Butter- 

 wort ") 



Pink, 172 



Pitcher-plant (Nepenthes, 

 Sarracenia), 219, 245, 293 



Pistil, 156 



Plane, 160, 242, 254 



Plankton, 63 



Plant-corals, 58 



Plants and animals compared, 



II, 12 



Plant-breeding, 294, 297, 298 

 Plasmodium, 27 

 Platystemon, 275 

 Pleurococcus, *55 

 Plum, 298 

 Plum-cot, 340 

 Podostemonacese, 169 

 Pogonia, 258 

 Poison ivy (Rhus), 258 

 Poison oak (Rhus), 274 

 Pollen, 125, 126 

 Pollen-sac, 123, 152 

 Pollen-tube, 125 

 Pollinium, 232 

 Polysiphonia, 189 



Pond-lily (see "Nuphar") 



Pond-weed, 161, 163 



Pond-scum (Spirogyra), 55, 

 203 



Poplar, Populus, 113, 154, 160, 

 171, 172, 242, 250, 254; P. 

 nigra, 320 



Poppy (see " Eschscholtzia") 



Porella, *93 



Portulaca, 172 



Postelsia, 59, ="191 



Potato, 286 



Prairies, flora of, 260 



Prevention of self-pollina- 

 tion, 230 



Prickly pear, 201 



Primrose (see " Primula ") 



Primula imperialis, 262 



Primus blackberry, 339 



Pronuba yuccasella, 233 



Protococcus, 81 



Proteacese, 246, 248, 253 



Protective devices, against 

 animals, 227 ; against ex- 

 cessive light, 206, 210 



Protoplasm, 4, 7, 8, 39; struc- 

 ture of, 8; water in, 39 



Pseudo-bulbs, 208 



Pteridophytes (see also 

 "Ferns"), 97, 100, 105, 113, 

 160, 162, 194, 238, 239; fos- 

 sil, 105 



Pteridosperms, 116, 131, 137, 

 162, 239, 241 



Puff-ball, 74 



Quercus, Q. Brittoni, 338 ; Q. 



Hid folia, 338; Q. Mary- 



landica, 338 

 Quinine, 282 



Rafflesia, 182, 216 

 Ragweed, 290 

 Ramie, 281 

 Ranales, 163 



Ranunculus (see " Butter- 

 cup") 

 Raspberry, 283, 297 



