LIGHT DISCRIMINATION IN THE ENGLISH SPARROW 109 



Before concluding the author wishes to express her deepest 

 appreciation of the valuable suggestions, criticism and encourage- 

 ment of Dr. M. E. Haggerty, who so kindly suggested and 

 directed this experiment. She is also greatly indebted to Dr. 

 Haggerty, Mr. William O. Trapp and Mr. George H. Hyslop, 

 who were the human subjects in this investigation. 



