JOURNAL OF ANIMAL BEHAVIOR 



Vol. 4 MARCH-APRIL, 1914 No. 2 



LIGHT DISCRIMINATION IN THE ENGLISH SPARROW 



EUPHA FOLEY TUGMAN, A.M. 

 From the Psychological Laboratory of Indiana University 



CONTENTS PAGE 



I. Introduction 79 



(1) Statement of the problem. 



(2) Previous experimental work. 



(3) History of the investigation. 



(a) Preliminary experiment. 



II. Method 83 



(1) Care of the birds. 



(2) Method of handling the birds. 



(3) Description of the apparatus. 



(4) Experimental procedure. 



(5) Calibration of the lights. 



III. Results 89 



(1) Threshold of discrimination. 



(a) Comparison with human threshold. 



(2) Method of learning. 



(a) Tables and results for each bird. 



(b) Comparison of results. 



(3) Incidental results. 



(a) Individuality. 



(b) Influence of former experiences. 



(c) Position habit. 



(d) Mental instability. 



(e) Relation of time to the failure or success of choice. 



(f) Effect of 48 hour interval between successive series. 



(g) Persistence of stimulation. 



IV. Questions suggested by this investigation 107 



I. INTRODUCTION 



(1) Statement of the problem. — This investigation was pursued 

 for the purpose of determining (1) the threshold of brightness 

 discrimination in the house (English) sparrow, and (2) the behav- 

 ior which the sparrow exhibits and the habits which it forms in 

 learning to make such discrimination. 



