Xi 
Parmelia, 353. 
Parnassia, 27, 230. 
Paronychia, 282, 338. 
Parthenocissus, 452. 
Paspalum, 193, 239, 318, 325, 479, 495- 
Passiflora, 52, 274, 306. 
Pastinaca, 52, 442. 
Patellaria, 85, 377- 
Pavonia, 28, 269. 
Pecopteris, 95. 
Pediastrum, 243, 244. 
Pedicularis, 269. 
Pellza, 182, 458, 497. 
Pellicularia, 296. 
Peltigera, 353, 354- 
Penicillium, 452. 
Pentagonia, 175. 
Penthorum, 481. 
Penstemon, 28, 94, 301, 362, 377, 378, 493- 
Peperomia, 413. 
Peperamium, 32, 34, 66, 186, 188, 189, 190, 191; 192, 
476, 480. 
Perezia, 269, 413. 
Perichzna, 76, 296. 
Perityle, 412, 413, 497- 
Pernettya, 138, 500. 
Peronospora, 298, 443. 
Pertusaria, 377. 
Petasites, 443. 
Petalostemon, 377. 
Petroselinum, 433- 
Peucedanum, 88, 94. 
Peziza, 296. 
Phacelia, 301, 305, 378, 493 495- 
Phalaris, 197, 198. 
Phallogaster, 225. 
Phaseolus, 126, 230, 233, 294, 304- 
Phezopteris, 67, 461, 462. 
Philibertia, 348. 
Philonotis, 378. 
Phippsia, 342. 
Phieum, 199, 239. 
Phlox, 56, aa, ha 
Phoebe, 497. 
Pholicta, 264. 
Phoma, 251, 296. 
Phragmites, 175, 202, 239) 443- 
Phryma, 175. 
Phyllanthus, 477, 482. 
Phyliites, 135. 
Phyllosiphon, 37- 
Phylloporina, 85. 
Phyllosticta, 249, 250, 341, 364, 443, 488, 497- 
Physalis, 53, 64. 
Physalospora, 442. 
Physaria, 94. 
Physarum, 78, 79, 82, 269. 
Physcia, 353. 
Physcomitrium, 366, 447. 
Physostegia, 57, 3% 
Phytolacca, 54, 237. 
Picea, 29, 42. 
Pilocereus, 182. 
Pilosella, 120. 
Pilularia, 141, 142, 144, 147, 148- 
Pinus, 19, 30, 41, 42, 44, 45, 56, 66, 97, 275, 395, 
. 4499497, 501. 
Piper, 413, 
Piptocarpha, 378. 
Piptomeris, 3o0r. 
queria, 269. 
Pistia, 364. 
Pincodians 97 
lacodium, 351, 352, 354. 
Plagiochila, 86, deg = 
Plantago, g, 54, ay. 236, 253, 295» 3772 409: 
Platanthera, 37, 38, 
Platanus, 94, Sis Ws, es 172. 
gt 244- 
Pleuropogon, 342. 
Pleurosigma, 245. 
Pleuretrema, 37°. 
Plowrightia, 304. 
Pluchea, 230, 235, 484. 
Plumbago, 139. 
Poa, 204, 205, 2395 2835 342, 495- 
Podostemon, 481. 
Peecilandra, 497- 
Pogonatum, 378. 
Pogonia, 32, 66 183, 184, 186, 189, 199, 191, 192, 
2372475» 480. 
Polanisia, 277. 
Polyblastia, 377- 
Polycarpon, 343- 
Polyedrium, 244. 
Polygala, 61, 230, 233, 269, 294, 481- 
Polygonatum, 66, 480, 487, 488. 
Polygonum, 54, 59, 65, 213, 214, 215, 216, 221, 223, 
231, 2379 409, 453, 480,'496. 
Polymnia, 4, 6, 63. 
Polypodium, 21, 67, 301, 362, 457, 478. 
Polyporus, 303, 494- 
Polysiphonia, 171. 
Polystichum, 464. 
Polystictus, 296. 
Pontederia, 66, 238, 295, 452- 
Populus, 43, 44» 46, 47, 48, 49, 50, 65, 164, 237- 
Portulaca, 52, 232. 
Potamogeton, 59, 66, 229, 238, 242, 269, 270, 283, 
472- : 
Potentilla, 62, 69, 37, 88, 94, 239, 233, 409» 481, 493- 
Prenanthes, 2, 6, 15, 17, 63, 499, 452» 484. 
Primula, 69, 223- 
Proserpinaca, 62, 234. 
Prosopis, 500. 
Protostigma. 434. 
Prototaxites, 134. 
Prunella, 483. 
Prunus, 28, 61, 161, 167, 230, 233, 263. 
Psammisia, 137- 
Pseudoleskea, 274- 
Pseudopecopteris, 95. 
Pseudotsuga, 131. 
Pseudovalsa, 341- 
Pseva, 281. 
Psilophyton, 27. 
Psilophytum, 414. 
Ptelea, 158, 167. 
Pteris, 67, 230, 405, 406, 458, 478. 
Ptiloria, 496. 
Puccinellia, 205. - 
Puccinia, 220, 298, 341, 348, 378) 4422 487, 489, 492- 
Pulsatilla, 87. 
Pycnanthemum, 236, 294. 
Pyrenula, 377. 
Pyrola, 57, 60, 64, 262, 282. 
| Pyrularia, 477, 480. 
Pyrus, 60, 62, 173, 233» 481- 
Quercus, 60, 65, 99, 164, 166, 274, 295, 318, 346, 388, 
413, 442, 480, 498. : 
Raciborskia, 80 
Racomitrium, 274. 
Radula, 86. 
Ramalina, 353- 
Ramium, 175. 
Ramona, 306. 
Ranunculus, 52, 56, 60, 212, 213, 231, 305, 364) 4°95 
496. 
Raphanus, 52, 126, 223, 232. 
Raphidium, 244. 
Raphidonema, 226. 
Raphidostegium, 274. 
Ravenala, 343. 
Ravenelia, 324. 
Reseda, 22. 
| Reticularia, 76, 80. | 
Rhamnus, 482. 
tr Sa.) 
ae ‘Rhamphospora, 364. 
