INDEX 



539 



Plum rot, 293, 294. 



Plums, 438. 



Plumule, 7, 8, 12, 13. 



Pod, 208, 209. 



Pogonatum, 351. 



Poinsettia, 406. 



Pollen, 143, 158, 161, 168, 182, 199. 



Pollen case, 144. 



Pollen grains, 144, 156, 159, 160, 199, 

 200, 391, 395, 400. 



Pollen sacs, 144, 158. 



Pollen tube, 200, 201, 393-400, 401, 

 411, 413. 



Pollination, 143, 159, 182-198, 392, 

 408. 



Pollination, artificial, 498. 



Pollinium, 183, 189, 193. 



Polygamous, 146. 



Polygonum, ovule of, 200. 



Polymorphic, 287. 



Polymorphism, 273. 



Polypetalous, 147, 156. 



Polypodiaceae, 360. 



Polypodium vulgare, 359, 362. 



Polypody fern, 358, 359. 



Polyporacese, 326. 



Polyporus, 326-328. 



Polyporus applanatus, 328. 



Polyporus borealis, 139, 140. 



Polyporus igniarius, 328. 



Polyporus mollis, 140. 



Polyporus pinicola, 327. 



Polysepalous, 147. 



Polysiphonia, 354. 



Polysiphonia nigrescens, 263. 



Polysiphonia violacea, 264. 



Polystichum acrostichoides, 360. 



Polytrichum, 346, 347. 



Pomaceae, 4, 36. 



Pome, 213. 



Pomelo, 442. 



Pond lilies, 458. 



Populus dilitata, 54. 



Pore fungi, 326-328. 



Postelsia, 258. 



Potassium, 124. 



Potassium nitrate, 125. 



Potato, 21, 24. 



Potato, experiment with, 51; propa- 

 gation, 51. 



Potato family, 446. 



Pouch, 209. 



Powdery mildews, 289-291. 



Prairie societies, 476. 



Prickly ash, 441. 



Prickly lettuce, 85, 218, 219. 



Primrose, 190, 198. 



Primula, 190. 



Privet, 446. 



Procarp, 261, 262. 



Profichi, 196. 



Promycelium, 305, 314, 318, 320. 



Pronuba, 185, 186. 



Prop roots, 34, 35. 



Propagative stage, 319. 



Protease, 133. 



Proteins, 19, 20, 24, 114, 127. 



Proterandry, 191, 407, 419. 



Proterogeny, 407, 419. 



Prothallium, 359, 364, 368, 371, 372, 



375, 37 6 , 379, 395, 39 8 , 4oo, 402, 



410. 



Prothallus, 359. 

 Protococcus vulgaris, 240. 

 Protococcoideae, 228, 240, 251. 

 iProtonema, 346, 350, 351. 

 Protonemal thread, 364, 366, 370. 

 Protoplasm, 3, 4, 5, 39, 40, 233-237, 



277. 



Protoplasm, assimilation by, 4. 

 Protoplasm, irritability of, 4. 

 Protoplasm, movement of, 4, 249. 

 Protoplast, 5, 257. 

 Prunes, 438. 



Prunus amygdalinus, 438. 

 Prunus persica, 437. 

 Prunus serotina, 439. 

 Prunus virginiana, 149. 

 Pseudomonas radicicola, 128. 

 Pteridium aquilinum, 360. 

 Pteridophyta, 225, 229. 

 Pteridophytes, 225, 357-386, 402, 



405, 410, 421. 



Pteris aquilina, 360, 362, 364. 

 Pteris cretica, 370. 

 Pteris serrulata, 364, 367, 369. 

 Ptomaines, 141. 

 Ptyalin, 133. 

 Puccinia graminis, 309. 

 Puccinia malvacearum, 320. 

 Puccinia podophylli, 319. 

 Puccinia rubigo-vera, 317. 

 Puccinia taraxaci, 319. 

 Puff balls, 321, 322, 329. 

 Pulvinus, 87. 

 Pumpkin, n, 12, 25. 

 Purslane, 52. 

 Putrefaction, 141. 



