INDEX. 



335 



Narcissus, etiolated, 57 ; flower of, 

 diageotropic, 194; leaf of for 

 elasticity experiment, 137 ; pol- 

 len of for chemotaxis, 217; sto- 

 mata of, 109 



Nasturtium officinale, used in De 

 Saussure's exp. , 74 



Negative pressure, 86, 87 



Nerium, see Oleander 



Nesslerising, precautions necessary 

 in, 256 ; see also Proteids, esti- 

 mation of 



Nitrate, diphenylamin reaction for, 

 67 



Nitrates, 253, 260, 315; estima- 

 tion of, 258, 259 ; in connection 

 with calcium oxalate, 67 



Nitrites, see Nitrates 



Nitrogenous plastic substances, 

 preparation of extracts for, 244 



Nitrometer, use of, 258, 279 



Nobbe's experiments on swelling of 

 peas, 113 n., 116,117; on imbi- 

 bition and temperature, 113 n. 



Noll, on growth of pulvinus in 

 grass-haulms, 166 



Non-nitrogenous plastic substances, 

 preparation of extracts for, 242 



Nutation of epicotyls, 198 ; revolv- 

 ing, 227 



Nyctitropic movements of Mimosa, 

 record of, 224 ; of Trifolium, 

 221; of Oxalis, Marsilea, Meli- 

 lotus. Cassia, Nicotiana, Brassica, 

 Eaphanus, 222, 223 



Oil (olive-), action of on chloro- 

 phyll solution, 50 



Oils, 261 ; extraction of, 245 ; sa- 

 ponification of, 262 ; estimation 

 of, 263, 264; experiments on, 

 265, 313, 316; see also Gly- 

 cerin 



Oleander used in assimilation ex- 

 periments, 44; for difl'usion, 

 49 



Oliver, on stigma of Mimulus, 211 



Onion, stomata of, 109 



Onobrychis, used in experiments 

 on nitrogenous metabolism, 259, 

 260 



Osmotic strength of cell- sap in 

 terms of KNO.j, 126 



Oxalic acid, 295, 297, 301 



Oxalis, leaf of, change of colour on 

 heating, 14 ; as indicator of 

 poisonous effect of phenol, 19; 

 injected leaf, affected by heat 

 more easily, 14; movement of 

 chloroplasts in leaves of, 214 ; 

 sensitive to touch, 205 ; used 

 for Briicke's experiment, 206 



Oxygen, evolution of by water 

 plants, 35, 39 ; affected by vari- 

 ous conditions, 37; method of 

 collecting, 38 



Palmitin, 263 



Paraheliotropism, 224 



Passiflora, tendrils of, 200 



Peas, imbibition of, 113; swelling 

 of testa of, 117 ; warmth pro- 

 duced by germinating, 11 



Pelargonium, nitrates in, 66 



Penicillium, culture of, 68 



Pentoses, see Sugars 



PejJtones, see Proteids 



Permeability of membranes, 88 



Petroleum ether, use of in extrac- 

 tion, 242 



Pfeffer on absorption of methylene 

 blue by Elodea, 124 ; on a cen- 

 trifugal machine, 170; on che- 

 motaxis, 214, 216; on effect of 

 chloroform on Mimosa, 211; on 

 method of estimating CO., assi- 

 milated, 41 ; on contact-stimu- 

 lation of Drosera, 208; on evo- 

 lution of gas by water plants, 

 35, 37 ; on use of gelatine in 

 experiments on tendrils, 201 ; 

 gypsum method, 131; on heat 

 produced during respiration, 12; 

 on intramolecular respiration, 

 10; on irritable stamens of 

 Centaurea and Cynara, 212 n.; 

 on Johnson's experiment with 

 geotropic roots, 167; on Knop's 

 formula for water culture, 59 n.; 

 on use of lime water in freeing 

 water from CO.,, 29; on open- 

 ing and closing' of flowers, 219- 



