INDEX 
Rédl, E., phototaxis of Arthro- 
poda, 55 
relation of phototaxis to vis- 
ion, 56 
Rae, Dr., fear in young ducks, 123 
Ranatra, behavior after decapita- 
tion, 105 
interference of reactions, 5, 
140 
phototaxis, 48, 51, 52, 55, 56, 
144 
Random movements, in chemo- 
taxis, 24-26 
in phototaxis, 21, 22, 41-45 
rdle of in learning, 168 
Rat, imitation, 255, 256 
Raven, imitation, 257 
Reason, in apes and monkeys, 
274 ff 
in insects, 203 ff 
in mammals, 232 ff 
Reflex action, 11 ff 
Reflexes, 2, 11 ff 
of pecking, swallowing, 176—- 
177. See also Motor 
Reflex. 
Reflex action and instinct, 99 ff, 
116, 117 
Reighard, J., 231, intelligence of 
fishes, 223, 224 
Reimarus, H. S., 114 
Reptiles, intelligence, 229, 230 
Reuter, O. M., intelligence of ants, 
193 
Rhea, no innate fear of man, 122 
Rheotaxis, 34, 37 ff, 57 
Rhesus monkey, intelligence, 262- 
265 
imitation, 271-274 
Rhumbler, L., 90, behavior of 
Ameeba, 68 
Rhythms, in behavior, 16, 79, 80, 
155-158 
Righting movements, in Loxo- 
phyllum, 81 
in starfish, 154, 155, 158 
293 
Romanes, G. J., 10, 114, 138, 279, 
animal intelligence, 2 
definition of instinct, 91, 92 
evolution of instinct, 120, 
121 
homing of bees, 196 
intelligence of dog, 250 
moth flying to candle, 20 
Romanes, Miss, intelligence of 
Cebus, 265, 269, 278, 279 
Sachs, H., tropisms, 19 
Sagartia, effect of hunger on food 
taking, 150 
geotaxis, 30 
Schaeffer, A. A., 90, 231, food tak- 
ing in Parameecium, 72 
selection of food in Stentor, 85, 
86 
intelligence of frog, 228, 229 
Schneider, G. H., 114, 190, in- 
stinct, 1 
intelligence of octopus, 188, 
189 
Schneider, K. C., 114 
Schrader, M., 17, segmental re- 
flexes in frog, 107 
Sense of direction, in ants, 193 
in bees, 193, 196-202 
in horses, 247 
in wasps, 193-196, 200, 
201 
Serpula, reactions to light and 
shadows, 41 
varied reaction to shadows, 
145 
Shepherd, W., 279, imitation in 
Rhesus monkeys, 272, 273 
Sherrington, C. S., 17, reflex action, 
11 
Small, W. S., 258, imitation in 
white rat, 255 
Smith, S., 90, educability of 
Paramecium, 86-89 
Sokolowsky, A., 279 
Solen, reaction to shadows, 41 
