THE DTSPI.AY OF ENKRCY 



:\m 



25'. 



14% 



5% 

 2% 



I.Q 69and below 70-79 80-89 90-99 I00-IO9 ilO-H9 120-129 laoondtip 



Distribution of intelligence in school children. I. Q.'s are shown below graph. 



SUGGESTED READINGS 



Caldwell, 0. W., Skinner, 0. E., and Tietz, J. W., Biological Foundations of 



Education, Ginn & Co., 1931. Chs. XIV, XV. 



An elementary luit valuable text. 

 Kohler, Wolfgang, The Mentality of Apes, Harcourt, Brace and Co., 1926. 



Fascinating reading. 

 Pavlov, I. P., Lectures on Conditioned Reflexes, International Publishing Co., 



N. Y., 1928, 



Authoritative and based on experimental evidence. 

 Walter, H. E., Biology of the Vertebrates, The Macmillan Co., 1929. Chs. 



XIX, XX. 



A well-established authority easily read. 

 Wells, H. G., Huxley, J. S., Wells, C. P.. The Science of Life, Doubleday, 



Doran & Co., 1934. Book VIII. 



Interesting discussion of consciousness in animals. 

 Wheeler, R. H., and Perkins, T. H., Principles of Mental Development, The 



Thomas Y. Crowell Co., 1932. Chs. Ill, V. 



An excellent exposition of gestalt psycholog>\ 

 Yerkes, R. M., and Learned, B. W., Chimpanzee Intelligence and Its Vocal 



Expression, Williams and Wilkins Co., 1925. 

 Yerkes, R. M., and Yerkes, A., The Great Apes, Yale University Press, 1929. 



Both of Dr. Yerkes' books give the latest experimental work on the emo- 

 tional and mental life of the apes. 



