52 CORA D. REEVES 



the discrimination compartment (2 fig. 1). They remained 

 for perhaps six to ten minutes quite motionless. Table II 

 in the column marked " time in seconds " shows these 

 delayed responses. " Not out of 2," in the table indicates 

 no response. 



In the case of Small Sunfish the usual time for response 

 in the blue-red series was eight to twenty seconds. In the 

 series described on page 38ff, I have records of 30 to 50 

 seconds, but none of 480 seconds and none of failure to 

 leave the discrimination compartment. 



Before testing Md with this blue-gray I had tested her 

 three times with red-gray, twice with this same gray against 

 very bright red, and once with the gray against a duller 

 red. She had gone each time to the gray and been fed. 

 The time for these successive responses was 20, 10, and 6 

 seconds. Her delay (70 and 230 seconds and refusal to 

 respond) when gray was substituted for the red, convinced 

 me that for this fish red difi^ered from a matched gray. 

 The fact that this fish had just been fed before the gray 

 may explain the continued gray response shown in Table 

 II. A somewhat lengthened time for response often oc- 

 curred in the blue-red series. This was more frequent on 

 the third or fourth test for the day than on the first, appar- 

 ently because hunger prevented delay in the first response. 

 By delay in response' these fish showed that the change 

 from light of longer wave-length to mixed light had been 

 effective in stimulating them. The light was evidently 

 the means of discrimination, and quality rather than in- 

 tensity was the effective stimulus. 



b. Peculiar Behaiior. — When the blue-gray patches were 

 exposed to the three sunfish, each advanced toward them, 

 halted, retreated, and acted now as Large Sunfish had 

 acted when the blue and red were first presented. The 

 behavior of Md when the blue-gray patches were first 

 presented was like her behavior when the bright red and 

 blue were first presented, some six months earlier. She 

 now, as then, swam back and forth across the discrimina- 

 tion compartment before the door and finally up toward 

 the gray patch where she had just fed. 



To summarize, the sunfish by peculiar behavior and 



