1918 Miles; on Behaznor of Blennies 



Table 1. Reactions of blennies to light and color; data in per cent 



In all of the experiments the blennies exhibited marked periods of 

 activity and rest to such a degree as to suggest a physiological cause. In 

 this instance the individuals stopped in first one compartment and then 

 in another. In 2 individuals the periods of rest lasted about 3 minutes 

 in each. 



Later about 20 individuals were added and time given to become 

 accustomed to the box. After a period of 3 days, while the color of the 

 individuals seemed in no way to affect the reaction, a common reaction 

 could be noticed. Although scattered, there were more blennies in the 

 red section than in any 2 others excepting the orange, and the orange 

 contained fewer than the red. The fact that the red and the orange 

 were the end sections probably affected the results. It should be noted, 

 however, that it was much more difficult to see dark objects over the red 

 background in water than in the other sections. 



From the above data blennies give a positive reaction to red light 

 and red background, but it is possible that such reaction is merely to 

 greater obscurity. In fact it would seem that selective reaction to back- 

 ground color, merely as such, is very weak or wanting, although there is 

 a definite positive reaction to obscure positions and subdued light. When 

 total darkness is approached the reaction is reversed. These facts, it 

 should be noted, show positive reaction to conditions found in the normal 

 habitat. 



Relation betzceen color of background and pigmentalion 



In the collection from various localities, tlie close e()rresj)ondence be- 

 tween the coloring of blennies and that of the surrounding vegetation con- 

 tinually presents itself. Gamble (3) found that fisli tend to become the 

 color of their surroundings but that they respond to the color of the back- 

 ground when exposed to light rather than to the color of the rays them- 

 selves. Starks (1911) reported finding red and green blennies in exactly 



