INDEX 
Morgan, C. Lloyd, 10, 114, 138, 190, 
animal intelligence, 248 
behavior of protozoa, 63 
consciousness in animals, 4 
deferred instincts, 96 
evolution of instinct, 121 
fear of hawks not innate, 123 
homing of limpets, 187-189 
imitation in chicks, 254 
intelligence in chicks, 165; in 
dog, 234, 235; in stickle- 
back, 226 
instinct and internal impul- 
sion, 108, 109 
intelligence in solitary wasp, 
203, 204 
Lamarckism rejected, 124 
organic selection, 136 
principle of, 159, 234 
varied behavior of Clepsine, 
111, 112 
Morgan’s law, 159, 234 
Morse, M., tidal rhythms of 
Littorina, 157 
Mosquitoes, geotaxis, 32 
reaction of larve to shadows, 
142 
Moth, tropisms, 18 
Motor reflex, in Euglena, 28, 44, 45 
in Loxophyllum, 79, 80 
in Parameecium, 15, 73, 74, 76 
in Stentor, 44, 81, 82 
Mound-building bird, instinct of 
flight, 97 
Murbach, L., geotaxis in Gon- 
ionemus, 30 
Mysis, geotaxis, 31 
Nagel, W. A., 61, food taking in 
anemones, 150, 151 
light reactions of molluses, 41 
Natural selection, origin of instinct 
by, 134 ff 
Necturus, intelligence, 227 
Nephelis, phototaxis, 44 
Nereis, thigmotaxis, 36 
291 
Nervous system, of crayfish, 101 
Nightingale, variation in singing 
instinct, 133 
Norman, W. W., pain sensations in 
lower animals, 8 
Notonecta, phototaxis, 55 
Nuel, J. P., 61 
Octopus, intelligence, 188, 189 
Ocypoda, intelligence, 184 
Odynerus, instinct, 118 
Oelzelt-Newin, A., 90, food taking 
in Loxophyllum, 80 
Orang, intelligence, 267 
Orbitolites, thigmotaxis, 34 
Orchestia, phototaxis, 46, 48, 49, 
51, 55 
Organic selection, 136-138 
Osborn, H. F., organic selection, 
136 
Osmia, parental instincts, 120 
Ostrich, imitation in young, 254 
Oxytricha, forming of groups, 24 
thigmotaxis, 35 
Pachygrapsus, intelligence, 187 
Pagurus, intelligence, 186 
Pain, 6, 164 ff 
Palemon, 32 
statocysts, 31 ff 
Palemonetes, change of photo- 
taxis, 49 
Paley, W., conception of instinct, 
108 
definition of instinct, 91 
Parameecium, behavior, 15, 35, 71 
chemotaxis, 21, 23-25, 27, 
75, 76 
choice of food, 72 
effect of hunger on, 150 
electrotaxis, 59, 60 
forming groups, 24 
geotaxis, 29, 30 
interference of reactions, 140 
modifications of behavior, 76, 
77, 140 
