Xili 
Placodium, 249. 
Plagiobothrys, 234, 346. 
Plagiochila, 99, 198, 270, 289, 389. 
Plagiothecium, 248. 
Planera, 332. 
Plantago, 46, 145, 260, 332, 349, 388. 
Plasmodiophora, 171, 195, 383- 
Plasmopara, 83. 
Platanus, 285, 379. 
Platygerium, 9. 
Platymiscium, 135. 
Platy stemon, 197. 
Pleospora, 298. 
Pleurolobus, 107. 
Pleurosigma, 28. 
Pleurotus, 25. 
Pleurozium, 248. 
Pluchea, 4, 91. 
Poa, 246, 261. 
Podophyllum, 376. 
Podostemon, 89. 
Pogonatum, 248. 
Pogonia, 88. 
Polia, 235. 
Polemonium. 34, 224. 
Polycarpon, 9. 
Polygala, 32, 50. 133, 280, 350. 
Polygonum, 10, 
259, 351, 385. 
Polymnia, 148. 
Polypodium, 25, 236, 246, 283, 386. 
Poly stictus, 162. ; 
Polytrichum, 70, 100, 248. 
Pombalia, 54. ~ 
Pongamia, 332. 
Populites, 380. 
Populus, 134, 244, 261, 331, 376. 
Porella, 99, 198, 247- 
Porliera, 237. 
Porophyllum, 151, 384. 
Porotrichum, 70. 
Portulaca, 46, 138, 146, 380. 
Posadza, 71. 
Potamogeton, 194, 340. 
Potentilla, 183, 196, 241, 335» 349» 35? 
Poterium, g1, 241. . 
Pottia, 275. 
Prantleia, 68. 
Prasiola, 347. 
Prenanthes, 231, 243, 335 
Pritchardia, 64. 
Prosartes, 26r. 
Prosopis, 29, 103, 383. 
Protzoides, 235. 
Protococcus, 119. 
Proustia, 266. 
Prunus, 134, 136, 276, 280, 349, 37, 399- 
Pseva, 60, 385. 
Pseudospora, 79. 
Psilostrophe, 59. 
Psoralea, 56, 91, 94- 
Psychotria, 58, 235. 
Psychotrophum, 58. 
Pterinodes, 65. 
Pteris, 182, 246, 260. 
Pterocaulon, 148. 
Pterophyllum, 343. 
Prterospora, 243. 
Pterosporopsis, 60. 
Ptilidium, 270, 
Ptilimnium, 57. 
Prilonella, 276. 
Ptychosperma, 86. 
Puccinia, 198, 232, 236- 
Pucciniosira, 136. 
Pulsatilla, 231. 
Purshia, 345. 
Pycnanthemum, 45, 62, 385- 
Pyrenochzta, 257. 
Pyrenophora, 162. 
Pyrola, 89, 183, 243. 
63, 68, Ot) 144, 161, 183, 244). 
2 Pyrus, 157, 162, 166, 280, 376. 
Quercus, 30, 31, 104, 134, 135s 137, 140, 162, 250, 
274, 300, 309, 332, 346, 379- 383) 388. 
Racomitrium, 247. 
Radiopaima, 133. 
Radula, gg. 
Raminium, 63. 
Ramularia, 25, 83- : 
Ranunculus, 93, 146, 187, 196, 219, 231, 234, 239) 
246, 259, 284, 297- 
Raphanus, 82, 145. 
Ravenelia, 232. 
Razoumofskya, 197- 
Reinechia, 86. 
Reseda, 382. 
Restrepia, 236. 
Rhatdochloa, 64. 
Rhamnites, 389. 
Rhamnus, 235- 
Rhinanthus, 61, 244. 
Rhipsalis, 103, 261. 
Rhizobium, 205. 
Rhizocephalum, 374. 
Rhizzolenia, 67. , 
Rhizophora, 29, 346, 387- 
Rhodea, 86. 
Rhododendron, 59, 149, 335- 
Rhodostachys, 68. 
Rhus, 55, 79, 103, 136, 322- 
Rhynchospora, 71, 233- 
Ribes, 94, 157, 24%) 3442 376- 
Richardia, 58, 86. 
Richardsonia, 58. 
Ricinocarpus, 02. 
Ridania, 385. 
Robinia, 32, 103, 136, 210. 
Romanzoffia, 184, 244- 
Romneya, 166, 261. 
Rosa, 32, t57, 161, 241, 349- 
Rosellinia, 203. 
Rostrupia, 277. 
Rothia, 59. 
Rottboellia, 64. 
Roubieva, 10. 
Rubus, 89, 98, 166, 181, 241, 383, 385- 
Rudbeckta, 45,95; 146, 388. 
Rudgea, 58, 235. 
Rumex, 138, 142, 193, 236, 244, 260. 
Rusbya, 72. 
Russula, 161. 
Sabadilla, 63- 
Sabazia, 384- 
Sabbatia, 64, 91, 359- 
Saccharomyces, 25. 
Saccorhiza, 72- 
Sagina, 91,249. 
Sagittaria, 194. 
Salicornia, 62, 68,91, 322- 
Salix, 244, 335, 343- 
Salmea, 150. 
Salvia, 278, 279- 
Salvinia, 65. 
Sambucus, 86, 181, 197, 242, 344, 349, 385- 
Samolus, gt. 
Sanguinaria, 258. 
Sapindus, 235, 343, 383 
Saponaria. g, 142, 391 
Sapota, 30. 
Sapotacites, 343- 
Saprolegnia, 135. 
Sarcobatus, 196 
Sarcodes, 60. 
Sarcodum, 60. 
Sarracenia, cg 87. 
Saxifraga, 68, 182, 196, 241. 
Scabiosa, 341, 389. 
Scapania, 247, 279- 
Scenedesmus, T19._ ¥ 
