598 



INDEX 



Peat Moss, 422. 

 Pectic substances, 277. 

 Pediastrum, 309, 308*. 

 Pediastrum boryanum, 308*. 

 Pedicels, 20, 20*. 

 Pedigree culture, 538, 578. 

 Penicillium, 375; described, 376, 376*. 

 Pepo type of fruit, 79, 78*. 

 Pepsin, 94. 

 Peptases, 284. 

 Peptones, 284. 

 Perennial stems, 171. 

 Perfect flower, 13, 11*. 

 Perianth, 11, 460, 11*, 460*. 

 Pericarp, 61, 66*. 

 Pericentral cell, 328. 

 Pericycle, 147. 

 Peridium, 390. 

 Perigynous flower, 16, 15*. 

 Perisperm, 46. 



Perisporiales, 364; described, 373- 

 375. 



Peristome, 421. 



Perithecium, 369, 370*. 



Permanent root, 103. 



Peronosporales, 353; described, 355- 

 360. 



Petal, 12, 11*. 



Petiole, 234. 



Peziza, 366, 367*. 



Pezizales, 364; described, 366-369. 



Phaeophyceae, 318-324. 



Phallus impudicus, 391, 392*. 



Phellogen, 185*. 



Phenotype, 536. 



Phloem, 130, 146, 188. 



Phosphorus, as a soil constituent, 158. 



Photosynthesis, 169; described, 252- 

 260; factors influencing, 257. 



Photosynthetic food, 273. 



Phycocyanin, 297, 324. 



Phycoerythrin, 324. 



Phycomycetes, 352; described, 353- 

 363. 



Phylogenetic divisions, 292. 



Phylogeny, 291. 



Phylloglossum, 438. 



Physical basis of heredity, 535. 



Phytophthora cactorum, 358, 361*. 

 Phytophthora infestans, 357, 358*, 



359*, 360*. 



Pigments, 274; described, 285. 

 Pileus, 386, 386*. 

 Pilobolus, 362. 



Pineapple type of fruit, 80, 80*. 

 Pine Blister-Rust, 402. 

 Pines (Pinaceae), 451-458; gameto- 



phytes, 455-457; life cycle, 457*; 



seed, 457; sporophyte, 452, 451*; 



strobili, 452-455. 

 Pink, family, 480; flower, 481, 15*, 



481*. 



Pistil, 11, 11*; compound, 15; de- 

 scribed, 14, 462; simple, 15; 



structure, 33-37. 

 Pistillate flower, 14, 12*; of Corn, 18, 



19*. 



Pitcher Plant, 132, 272*. 

 Pith, 187, 187*. 

 Pitted vessels, 188, 190*. 

 Placenta, 77, 34*. 

 Plagiotropism, 173. 

 Plants and animals in soils, 155- 



158. 



Plant Breeding, 575-583. 

 Plant Ecology, 2. 

 Plant food, nature, 120. 

 Plant Geography, 3. 

 Plant Pathology, 2. 

 Plant Physiology, 2. 

 Plant succession, 510-512. 

 Plasmopara Viticola, 355, 355*, 356*, 



357*. 



Plastids, 115, 251. 



Plectascales, 364; described, 375-377. 

 Pleurococcus vulgaris, 294, 307, 294*, 



307*. 



Plowrightia morbosa, 369, 370*. 

 Plum type of fruit, 78, 77*. 

 Plumule, 56, 466, 56*, 466*. 

 Podophyllum, 180, 180*. 

 Poisonous Toadstool, 384*. 

 Pollen, 41, 41*, 42*; function, 42; in 

 . relation to external factors, 49; 



structure, 41, 42*. 

 Pollen chamber, 448, 449*. 



