INDEX 
633 
Nitrobacter, 83 
Nitrogen cycle, 318, 319 
Nitrosomonas, 82 
Nodules, 83 
Nomenclature, 4 
Nostoc, 215, 333, 341 
Nourishment, growth and, 123 
Nuclear division, indirect, 184 
Nucleolus, 1 6 
Nucleoplasm, 16 
Nucleus, 1 6 
Nutrition theory, 91 
Osmosis, 55, 56 
demonstration of, 57 
importance of, 59 
Osmunda cinnamomea, 159 
claytonia, 152, 160 
Ostrich fern, 114, 178 
Ovary, 436 
Ovules, 436 
Ovum, 170 
Oxalis, 138 
bupleurifolia, 122 
Oxidase, 79 
Oak, 34, 336 
Oats, smuts of, 297 
(Enothera, 470 
biennis, 471, 534 
brevistylis, 533 
gigas, 535, 536 
Lamarckiana, 532, 533, 533 
Oleander, 39 
Onagra, 470 
Onagraceae, 470 
Onion, 348 
Onoclea, 172 
struthiopteris, 114, 178 
Ontogeny, 504 
Oosperm, 173 
Operculum, 202 
Ophioglossum, 178, 214 
vulgatum, 175, 177 
Opuntia Blakeana, 342 
Orange, 295 
Orchidaceae, 497 
Orchids, 327, 500, 501 
Organic and inorganic, 69 
Organisms, 8 
Organs, 7 
essential, 448 
Orobanchaceae, 338 
Paleobotany, 5, 578 
Paleogeography, 584 
Palisade, 35 
Palmaceae, 495 
Palmetto, sabal, 498 
Palms, barragona, 498 
cocoanut, 497 
Pandorina, 405 
Pangens, 565 
Papaw, 359 
Papillionoideae, 467 
Pappus, 487 
Paraphyses, 331, 380 
Parasites, artificial, 341 
fungal, 342 
Parasitism, 325, 339 
facultative, 343 
obligate, 343 
Parenchyma, 35 
Parmelia perlata, 330 
Parthenogenesis, 357 
Pasteur, 89, 98, 307 
Pea, 123 
edible, 468, 554 
Peach, brown rot of, 293 
leaf-curl, 293 
Pear blight, 309 
