Abstraction, 120. _See also_ Reasoning.
Action-system, importance of the study of the, 15 f.; of monkeys, 190 f., 237.
Anecdotal school in animal psychology, 23 ff., 151 f.
Apparatus, descriptions of, 29 ff., 56 ff., 61 f., 169 f., 177 ff., 196 ff.
Assimilation, 249 f.
Association, as a problem in animal psychology, 20 ff.; by similarity, 116 ff.; complexity of, 132 ff.; conditions of, 43 ff.; delicacy of, 128 ff., 195 ff.; development of, in the animal kingdom, 285 ff.; in cats, 38 ff.; in chicks, 63 f.; in dogs, 56 ff.; in fishes, 169 ff.; in man, 123 ff., 127, 285; in monkeys, 182 ff., 194 f., 209 ff.; in relation to attention, 44 ff.; to individual differences, 52 ff.; to inhibition, 142 ff.; to instincts, 36 f., 142 ff.; to previous experience, 48 ff.; number of connections formed by, 135 ff.; permanence of connections formed by, 138 ff., 194 f., 203 f.; progress of, measurable by time-curves, 28, 40, 42; the mental fact in, 98 ff.; without ideas, 101 f., 127, 209 ff. _See also_ Associations and Learning.
Associations, complexity, 132 ff.; delicacy, 128 ff., 195 ff.; number, 121, 135 ff.; permanence, 138 ff., 194 f., 203 f.
Associative memory. _See_ Association.
Attention, 144 ff.; and association, 44 ff.; to imposed movements, 103 ff.
Behavior, acquired tendencies to, 244 ff. (_see also_ Association); evolution of, 272 ff.; general laws of, 241 ff.; indefiniteness of the term, 5; of cats, 35 ff., 88 f., and _passim_; of chicks, 63 f., 138, 143 f., 156 ff., and _passim_; of dogs, 59 ff., 92 ff.; of fishes, 169 ff.; of monkeys, 182 ff.; original tendencies to, 242 f. (_see also_ Instincts); predictability of, 241 f.; proposed simplification of the laws of, 265 ff.; _versus_ consciousness as an object of study, 1 ff. _See also_ Association, Instincts, Learning, Memory, etc.
