162 UPLAND AND MEADOW. 



evidently under the fish's control, and are intelligently 

 used to its advantage. 



The bony gar is another fish having decided control 

 over the coloration of its scales. When this fish is at rest 

 the scales are pale blue, with a pink margin ; and about 

 the head and gill-covers there is a variety of brilliant 

 hues. At times all these colors will suddenly disappear, 

 and the fish has much more the appearance of a water- 

 soaked stick than of a living animal. Unfortunately, I 

 have had too few opportunities for observing this species 

 to determine the reasons for these changes; but it is 

 evident that they are under the control of the fish, 

 and therefore advantageous. 



The common pike also exhibits a variation of color- 

 ing, under different circumstances, and suggests the same 

 facts that have already been stated with regard to other 

 species. 



"When the chief aim of biological science seemed to 

 be the naming and describing of " species," it was found 

 that no description of the color of a fish, unless very 

 unusual and marked, was at all satisfactory. Consider- 

 ing the subject of color, as I have here done, the cause 

 is very evident. 



A few fishes which had escaped both my first and 

 second examination of the mass of aquatic plants yet 

 remained in the refuse left by the fishermen, after the 

 drawing of the seine. These were very young eels. 

 These little specimens were enveloped in the slimy 

 mass of leaves of the Nuphar pumilum; a splatter-dock 

 which retains its foliage below the water's surface and 

 which is but a mass of pulp when brought into the air. 



