INDEX 



635 



Pollen-grain, 401, 436 

 Pollen-sacs, 436 

 Pollination, 401, 427 

 Pollinium, 477, 501 

 Polypetalae, 456 

 Polypodium, 154, 156, 159 

 irioides, 154 



punctatum, 153 

 Polytrichum commune, 206 

 Populus, 457 



Porella navicularis, 211, 212 

 Potato, 335, 347, 480 



blight, 313 



rot, 292 



tuber, 81 



Potatoes, little, 291 

 Potoni6, 598 

 Pressure, osmotic, 58 



and growth, osmotic, 113 

 Priestley, Joseph, 73, 74 

 Primofilices, 616 

 Proangiosperms, 606 

 Propagation, 180 

 Prophylaxis, 310 

 Protease, 79, 86 

 Protein, 16 

 Proteins, 71 



manufacture of, 84 

 Prothallus, 166, 167 

 Protonema, 165, 166 

 Protoplasm, 14, 15 



properties of, 19 

 Protoplast, 1 6 

 Pseudoborniales, 618 

 Pseudomonas radicicola, 82, 83, 



3i8, 332 



Pseudopodium, 200, 201 

 Psilotales, 618 

 Pteridophytes, 366, 388 

 Pteridosperms, 592 



significance of, 598 

 Pteris, 156 



Pteris aquilina, 149, 155 



longifolia, 153 

 Pteropsida, 616 

 Ptyalin, 100 

 Puccinia graminis, 299 

 Punk, 303 



Purity of gametes, theory of, 555 

 Pussy-willow, 458 

 Putrefaction, 319 

 Pyrenoids, 353 

 Pyrolaceae, 473 

 Pythium de Baryanum, 291 



Quarantine, 311 

 Quercus, 336 



novimexicana, 34 

 Qu6telet, 524 

 Que"telet's curve, 525, 526 



Radicle, 381, 464 

 Ranunculaceae, 459 

 Ranunculus, 459, 460, 461, 462 



aquatilis, 507 

 Rattan, 495 

 Rattlesnake fern, 176 

 Ray, John, 453 

 Recptacle, 155 

 Redi, 89 

 Reduction, 183, 184 



division, 185, 187 

 Regeneration, 205 

 Reproduction, asexual, 179 



by spores, 180 



cell-division and, 344 



essence of all, 180 



inheritance and, 544 



sexual, 179, 1 80 



