484 GERTRUDE MAREAN WHITE 



them nearly every day from forceps. It was very amusing to see 

 all fourteen of them dart to the top at a slight movement of anyone 

 near them and begin sticking their noses out of the water in 

 anticipation of food. When food was held a slight distance out 

 •of water, they would with one accord leap out after it, and at 

 times hang on so tightly that they could be lifted several inches 

 out of the water before letting go their hold. 



On one occasion, after the sticklebacks had been given a 

 small piece of calves' liver, the forceps were held out to them 

 empty. None of the sticklebacks approached the forceps, but 

 the merest bit of dark red liver was sufficient to attract them, 

 A bit of rather bright red paper rolled into a ball and substi- 

 tuted for the food was at once attacked. Tan-yellow presented in 

 the same way elicited no positive response. Lavender which had 

 a pinkish tinge was snapped at twice, while dark blue, gray, 

 yellow, and green failed to attract. When dark red paper, 

 which most closely resembled the color of the liver, appeared the 

 fishes darted towards it from all directions seizing it voraciously. 

 Reddish purple was snapped at several times. These papers 

 were compared with Klingsiek and Valette's Code de Coleur 

 :and were found to resemble most closely the following numbers: 



Dark red — rouge no. 3 



Red — rouge no. 6 



Tan-yellow — orange no. 146 



Yellow — orange-jaune no. 166 



Green — vert no. 301 



Blue — bleu violet no. 452 



Gray^bleu violet no. 460 



Lavender — violet no. 528B 



Purple — violet rouge no. 571 

 This experiment indicates that the color of the food which 

 sticklebacks take habitually makes an impression difficult to 

 eradicate. Red no. 6 seemed to the eye to be very bright; red 

 no. 3 was quite as dark as blue no. 452, and not so dark as gray 

 no. 460 which was rejected. 



