362 



INDEX 



Peronospora, 142, 



Petal, 221, 222. 



Petiole, 6. 



PhaeophycesB, 116. 



Phloem, 52; root, 74. 



Photosynthesis, 18, 87. 



Phototropism, 92. 



Phycomycetes, 144. 



Pileus, 155. 



Pine, timber, 218. 



Pineapple, 281. 



Pirus, 289. 



Pistil, 228. 



Pitcher-plant, 35. 



Pith, 50; ray, 51. 



Plains, 341. 



Plant associations, 324; cactus 

 desert, 341; deciduous forest, 

 350; mangrove swamp, 336; 

 meadow, 345; mesophytic thick- 

 et, 348; peat-bog, 336; plain, 

 341; pondweed, 328; reed- 

 swamp, 331; rock, 338; salt and 

 alkaline desert, 344; salt marsh 

 and meadow, 336; salt steppe, 

 344; sand, 338; subtropical 

 desert, 341; swamp, 331; swamp 

 forest, 336; swamp thicket, 332; 

 tropical forest, 355; xerophytic 

 forest, 344; xerophytic thicket, 

 344. 



Plant-breeding, 316. 



Plasmolysis, 115. 



Plastid, 104. 



Pleurococcus, 102. 



Plum, 289. 



Plumule, 86; escape of, 91. 



Pod, 238. 



Pollarding, 70. 



Pollen, 242; Angiosperm, 224; 

 conifer, 212. 



Pollen-sac, 226; conifer, 212. 



Pollen-tube, Angiosperm, 236; 



conifer, 217. 

 Pollination, Angiosperm, 242; 



conifer, 217. 

 Pollinium, 248. 

 Pome, 289. 

 Pomelo, 299. 

 Pomology, 289. 

 Pond-scum, 113. 

 Pondweed association, 328. 

 Pore Fungi, 156. 

 Potato, 305. 

 Prairie, 345. 

 Profile leaves, 29. 

 Pronuba and Yucca, 244. 

 Prop-root, 80. 

 Protection, leaves, 24. 

 Proteid, 88. 

 Prothallium, 193. 

 Prothallus, 193. 

 Protoplasm, 87, 103. 

 Prune, 289. 

 Prunus, 288. 



Pteridophytes, 183, 207, 208 

 Puffball, 158. 

 Pumpkin, 315. 

 Pyrerioid, 114. 



Quince, 291. 

 Quinine, 309. 



Raceme, 232. 

 Rain, leaves, 32. 

 Ranunculacese, 284. 

 Raspberry, 287, 

 Ray, 310. 

 Reaction, 93. 

 Receptacle, 240. 

 Red Algae, 124. 

 Redwood, 219. 

 Reed swamp, 331. 

 Reforestation, 323. 



