358 LIGHT AND THE BEHAVIOR OF ORGANISMS 



tlon. Bateson (1887) records similar results in work on 

 Stenorynchus. Recently I have again tested crabs for 

 selection of color. At the Tortugas Islands numerous 

 specimens of each of three species, not yet definitely 

 identified, were used in these tests. A large proportion 

 of all of the animals observed decorated profusely in the 

 colored aquaria used; but I found no evidence whatever 

 of harmony between the color of the substance selected 

 and that predominating in the environment, although the 

 methods used by Minkiewicz were closely imitated. 



4. Fishes 



I shall refer to but two other experiments on the subject 

 of reactions to colors, one by Washburn and Bentley on 

 the creek chub Semotilus atromaculatus, the other by 

 Reighard on the marine gray snapper, Lutianus griseus. 



Washburn (1908, p. 140) gives the following description 

 of their experiment: '' Two dissecting forceps were used, 

 alike except that to the legs of one were fastened, with 

 rubber bands, small sticks painted red, while to those of 

 the other similar green sticks were attached. The forceps 

 were fastened to a wooden bar projecting from a wooden 

 screen, which divided the circular tank into two compart- 

 ments, and hung down into the water. Food was always 

 placed in the red pair of forceps, which were made fre- 

 quently to change places with the green ones; and the fish 

 was caused to enter the compartment half of the time on 

 one side and half of the time on the other. This was to 

 prevent identification of the food fork by its position or 

 the direction in which the fish had to turn. The animal 

 quickly learned to single out the red fork as the one impor- 

 tant to its welfare, and in forty experiments, mingled with 

 others so that the association might not be weakened, 

 where there was no food in either fork, and where the for- 

 ceps and rubber bands were changed so that no odor of 

 food could linger, it never failed to bite first at the red. 



