Nandina, 253 Narcissus, 446 Nasturtium, 337 Nectarine, 62 Nectary, 12 Negundo, 321 Nelumbium, 257 Nemophila, 410 Nepenthes, 429 Nerine, 446 Nerium, 402 Nettle, 158 Nettle Tree, 432 New Jersey Tea, 346 New Zealand Flax, 449 Nicotiana, 148 Nierembergia, 150 Night-flowering Cereus, 370 Nightshade, 143 Nitella, 465 Nitraria, 367 Nitrogen, 267 Nolana, 155 Noli-me-tangere, 338 Nopal tree, 371 Norfolk Island Pine, 220 Norway Maple, 319 Nuphar, 256 Nutmeg, 425 Nux vomica, 401 Nuytsia, 385 Nyctagineæ, 420 Nymphæa (_fig._ 110), 254 Nyssa, 427 O. Oak (_figs._ 85, 86), 190 Oak Apples, 195 Oak Wood, mode of testing, 194 Oats, 458 Ochnaceæ, 342 Œnothera (_fig._ 33), 80 Ogechee Lime, 428 Olax Tribe, 307 Old man, 107 Oleander, 402 Oleaster, 428 Olive, 137 Onagraceæ, 354 Onions, 449 Opercularieæ, 387 Opium, 263 Opium Poppy (_fig._ 112), 262 Opuntia, 371 Orange (_figs._ 121 and 122), 307 Orange Lily, 450 Orchidaceæ, 438 Orchil, 469 Orchis, 439 Ornithogalum, 449 Orobanche, 416 Oryza (Rice), 459 Osage Orange, 170 Osier, 184 Osmunda, 463 Ostrya, 202 Osyris, 427 Ovary, 5 Ovules, ib. Oxalis, 339 Ox-eye Daisy, 105 Oxycoccus, 131 P. Palea (_fig._ 45), 103 Paliurus, 345 Palma Christi, 431 Palm Trees, 452 Palo de Vacca, 166 Pancratium, 446 Pandamus, 453 Papaw Tree, 361 Paper Mulberry, 169 Papilionaceous Flowers (_fig._ 13), 36 Pappus, 98 Papyrus, 457 Parnassia, 284 Parsley Tribe, 378 Partridge Wood, 307 Passerina, 427 Passion Flower, 361 Pasque Flower, 19 Patersonia, 443 Paulownia, 412 Pavia, 326 Peach, 61 Pear (_fig._ 28), 67 Pedalineæ, 405 Pedicel, 47 Pelargonium (_fig._ 134), 332 Pellitory of Spain, 105 Pellitory of the wall, 163 Pendaceæ, 396 Pentstemon, 412 Peony (_fig._ 6), 18 Pepper, 432 Pepper-grass, 464 Perennial Flax, 295 Pereskia, 371 Pergularia, 403 Perianth, 7 Periploca græca, 403 Peristome, 467 Persicaria, 423 Persimon, 400 Personate corolla, 411 Peruvian Bark, 86 Petaloid, 237 Petals, 7 Petty Whin, 40 Petunia, 149 Peziza, 471 Phacelia, 410 Phœnix dactylifera, 453 Phanerogamic Plants, 236 Pharbitis, 408 Philadelphus, 358 Phillyrea, 137 Phlox, 406 Phormium, 449 Photinia, 72 Phyllodia (_fig._ 15), 42 Physalis, 145 Physianthus, 403 Phyteuma, 394 Phytolacca, 421 Picea, 214 Pileus, 470 Pilewort, 17 Pillwort, 464 Pimelea, 427 Pimpernel, 417 Pinaster, 211 Pinckneya, 88 Pine and Fir Tribe, 208 Pine Apple, 451 Pinguicula, 416 Pink, 292 Pinnæ, 43 Pinnate leaf, 252 Pinnatifid leaf, 69 Pinus, 209 Pipewort, 456 Pistacia, 348 Pistil (_fig._ 1), 5 Pitch, 209 Pitcher Plant, 429 Pittosporum, 287 Placenta, 37