INDEX 



403 



and Stentor, 195, 197; trial and 

 error, 196, 197; circus movements, 

 216; 257-260; 270; change in re- 

 actions, 285; 346. 



Mustard. See Sinapis. 



Myxomycetes, 74; 229; 233; adapta- 

 tion, 237. 



Nageli, early observations on move- 

 ment of flagellates and swarm- 

 spores, 14; 15; effect of light in- 

 tensity on rate of movement, 100, 



Nagel, 58; 247; on reactions td 

 shadows and acclimatization, 248; 

 250; 251; effect of different rays 

 on reactions, 302. 



Narcotics, effect of, on reversal of 

 reactions, 279-283, 300. 



Natural selection and adaptation, 

 238, 239, 272. 



Nemertean, 355. 



Nernst glower, 61; 86; 92. 



Newcombe, transmission of stimuli, 



59- 

 Nichols, distribution of energy in 



spectrum, 304, 305. 



Oats. See Avena. 



Oedogonium swarm-spores, orienta- 

 tion in light from two sources, 87; 

 description of, 123, 124; collection 

 of material, 124; locomotion of, 

 124; reversal in sense of orienta- 

 tion, 125; mechanics of orienta- 

 tion, 126-128; aggregation of, 127, 

 241; 229. 



Oltmanns, experiments on ray direc- 

 tion and intensity difference, 39, 

 40; 42; 60; 63; 265; 290. 



Optimum intensity, effect of, on 

 aggregation, 242; variation in, 

 288-297, 301. 



Orchestia, reversal in reactions, 271, 

 284, 300. 



Orientation in light, in plants and 

 animals compared (Loeb), 24, 25; 

 plumules of Zea mays: 63-69, dis- 

 cussion of, 70-71; in leaves, 71-73; 

 in Amoeba: 76-79, discussion of, 

 80; in Euglena (Jennings), 83, 84; 

 from two sources (Euglena, etc.), 

 86-89, 219-221, 224; accuracy of, 

 in Euglena, 92; mechanics of, in 

 Euglena crawling, 92-99; discus- 

 sion of, in Euglena, 99-102; in 

 negative Euglena, 99; mechanics 

 of, in Euglena swimming, 102-104; 

 mechanics of, in Oedogonium 

 swarm-spores, 126-128; in Trache- 

 lomonas: accuracy of, 129, me- 

 chanics of , 129, 130; mechanics of, 

 in Chlamydomonas, 132, 133; me- 

 chanics of, in Volvox, 137-144, 

 231; in Volvox compared with 

 that in Euglena and Stentor, 142; 

 in Eudorina and Pandorina, 147, 

 231; in Hydra, 157, 231; in Euden- 

 drium planulae, 161-163; in Eu- 

 dendrium hydranths, 163, 164; 

 in Arenicola larvae, 167-171, 232; 

 in Musca larvae, 189-197, 232; 

 in earthworms, 198-205, 232; in 

 Echinoderms, 21 1-2 13; in Bufo, 

 219-223; in Caprella, 224, 225; 

 in Corethra larvae, 225; in lobster 

 larvae, 226; in zoeae of Brachyura 

 and Caridea, 226; mechanics of 

 (general), 233-235; effect of, on 

 aggregation, 241-244; fundamen- 

 tal cause of, 243; in Daphnia, 

 264. 



Oscillaria, reactions of, in spectrum, 

 323, 326, 327, 362; distribution of 

 stimulating efficiency in spectrum, 



Ostwald, 265. 



Oxygen, effect of, on reactions, 279, 

 323-325, 362, 374- 



