468 



INDEX. 



Plumule, 116, 364, 396 

 Pod, 116, 365, 423 

 Polar nucleus, 105, 106 

 Polemoniales, 442 

 Pollen grains, 102 

 Pollinium, 391, 392, 441 

 Polygonales, 403 

 Polypodium, 298 

 Polyporaceae, 233 

 Polysiphonia, 192, 194 

 Polytrichum, 274, 275, 278, 282 

 Pond scum, 166 

 Poplar order, 396 

 Poppy order, 410 

 Pore, 11, 79, 33* 

 Porella, 262 



Potato, 448 

 rot, 199 

 Primrose order, 440 



Primulales, 440 



Pro-embryo, 327, 339, 362, 364 



Prosenchyma, 11 



Proteids, 16 



Protandrous, 349 



Protection of microspores, 379 



Proteid grains, 18, 19 



Prothallium, 283, 299, 300 



Protogynous, 349 



Protonema, 280 



Protoplasm, function of, 3 

 nature of, 2, 3 



Protoplasmic connection of cells, 3 



Pteridophyta, 282 



Pteridium, 298 



Ptomaines, 143 



Puccinia, 221, 224 



Puff ball, 234, 235 



Pulvinus, 30 



Pustules, 226, 227 



Pycnidium, pycnidia, 222 



Pyrenoids, 165, 166 



Pyrola, 351, 437 



Pyronema, 219 



Quercus, 350, 399, 401 



Ragweed family, 458 



Ranales, 404 

 Ranunculus, 406 

 Ray, flower, 456 



medullary, 7<j 

 Rattlebox, yellow, 446, 447 

 Receptacle, 348-353 

 Red algae, 154, 189-194 

 Red snow, 157 

 Respiration, 20, 46 

 Reproduction, 101, 124 

 Rhamnales, 428 

 Resin, 332 



Resurrection plant, 314 

 Rbinanthus, 446, 447 

 Rhizoids, 242 

 Rhizomes, 94, 95, 373 

 Rhizopus, 202, 203 

 Rhodophyceae, 189, 190 

 Rhus, 427 

 Riccia, 245 



Ricciocarpus, 245, 246, 254 

 Richards, 100 

 Ring, annual, J7 

 Rivularia, 147 

 Root, 1, 4, 42, 265, 283 



anchoring and suppdrting, 60 

 bacteria on, 57 

 contraction of, 60 

 lateral, 53 

 modification of, 56 

 sensitiveness of, 54 

 structure of, 50, 51, 52 

 surface of, 47, 48 

 Roots as storage organs, 59 

 Root cap, 50, 364 



hairs, 42, 43, 44 

 Rootstock, 94 

 Rosales, 414 

 Rosette, 27 

 Rose order, 414 

 Rostellum, 391. 392 

 Rubiales, 448 

 Rusts, 221 



white, 199 



Saccharomycetes, 206 



Sac fungi, 205-221 



