INDEX. 



335 



Narcissus, etiolated, 57 ; flower of, 

 diageotropic, 194; leaf of for 

 elasticity experiment, 137 ; pol- 

 len of for chemotaxis, 217; sto- 

 rnata 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 diffusion, 

 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 KN0 3 , 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, 1.1 



Pelargonium, nitrates in, 66 



Penicillium, culture of, 68 



Pentoses, see Sugars 



Peptones, 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 C0 2 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 beat 

 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 a for- 

 mula for water culture, 59 n., 70; 

 on use of lime water in freeing 

 water from C0 2 , 29; on open- 

 ing and closing of flowers, 219- 



