Index 
Smaxz, W. S., 173. 
SuiTH, S., 269 f., 280. 
Social consciousness of animals, 146 f. 
SPALDING, D. A., 162, 163, 165. 
Srovt, G. F., 3. 
Swimming, by chicks, 161 f. 
Time of achievement as a measure of 
the closeness of association, 28, 40, 42, 
54. 
207 
Time-curves, 38 ff., 57 ff., 65, 185 f£.; as 
evidence against the existence of 
reasoning, 73 f. 
TrtcHENER, E. B., 2. 
Vigor, as a factor in learning, 46. 
Wurman, C. O., 275 ff. 
Yerxes, R. M., 240. 
