ASSOCIATION AND COLOR DISCRIMINATION 



463 



Red no. 70: 640^ to 730/x 

 Red no. 71: 600^ to 730m 



Orange no. 72: 580m to 630m 660m to 710m = 



YeUow no. 73: 550m to 630m 570m to 720m : 



Green no. 74: 510 to 570m 



Green no. 75: 460m to 540m ) 



Blue no. 76: 420m to 480m 

 A flashlight was fitted out with a tin hood like the accom- 

 panying diagram (fig. 2). The hood, H, was slipped over the 



Fig. 2 Flashlight with hood, H, attached at the end to hold the gelatin filters, 

 F . The light shines through the filters at the opening, O. 



end of the flashlight and the monochromatic gelatin filter inserted 

 in a groove in the end of the hood where it could be locked in 

 position, F. The light was directed from above on the vessel 

 containing the fishes and food offered from forceps held beneath 

 the light. The experiments were performed at twilight during 

 the summer months. Of six mudminnows which were fed at 

 the beginning,* only three ate regularly enough to give results 

 of value. As before, the fishes were made to spring out of the 

 water after their food, and paper which matched the food was, 

 offered on the color which was to be refused. 



