220 Journal of Comparative Neurology and Psychology. 



peated. He then learned, in the course of a few minutes, to point 

 out the red spots on the other cubes, making, however, several 

 errors. It is worthy of note that, in these first experiments, 

 "orange" was often indicated as "red," a confusion which 

 occurred less and less often. I repeated the questions several 

 times the same day and the day following, always carefully avoid- 

 ing fatigue by making the actual test-period short. Even in later 

 experiments, as well as in these earlier ones, a test seldom lasted 

 more than one or two minutes. 



On the third day I showed the child a fairly large number of 

 colored paper squares, usually twenty at once, each square meas- 

 uring about four centimeters on a side. In the first experiments 

 with these squares I merely asked, "where is red.^" At the very 

 beginning the first three or four requests for " red " received correct 

 answers; then, however, fatigue or distraction had set in, and 

 the answers became either quite incorrect or were wholly wanting. 

 I was surprised that the child pointed, not only at brilliant red, 

 but likewise at rather unsaturated strawberry-red ("fraise"). 



On the following day the results were even more favorable. 

 Each time he was tested he designated without an error all the 

 papers in the collection that were red, and surprised me again by 

 including in his choice a fine purple-red and even a very bright 

 pink. 



The next four or five days were devoted to a repetition of the 

 same experiments. I showed the child the colors three times 

 daily, on an average, and received in all cases, even when others 

 were present, correct answers to the five or six questions that were 

 necessary to enable him to find all the red pieces of paper. I 

 always took away each piece that he had called red before asking 

 the next question. In these tests there were, among the reds, 

 likewise browns, greens and blues, all in various degrees of 

 brightness and saturation. 



From the fact that in answering the several hundred questions 

 which I put to the child during the tests he not once confused red 

 with brown or green, one may with certainty conclude that his 

 was no case of red-green color-blindness. For me, a deuteranope 

 (green-blind), the strawberry-red was only with great difficulty 

 distinguished from a bright brown, and a protanope (red-blind) 

 would have confused it with a somewhat darker shade of brown, 

 which was also to be found among the colors shown. Further, 



