BRIEF NOTES ON FISHES. 373 



diurnal. It has a green back, red vertical fins, and a 

 bright yellow-red belly, with deep blue on the sides, blue 

 stripes on the head, and a long, velvety black ear-flap. 

 Now, the spring and summer through, this fish seeks 

 clear, running water, and therein sports the day long, 

 leading very much a butterfly-like existence. 



In April, the colors, always bright;, are more brilliant 

 than ever, and it is at this time that it becomes evident 

 that the fish realizes what color is, and puts to good use 

 all the attractions that sexual selection has evolved. 

 Seeking some female of its kind, it displays itself by a 

 series of graceful manoeuvres, which are highly entertain- 

 ing even to outsiders. Passing to and fro before the 

 desired female, the fish will at times swim upon one side 

 so that the sunlight will strike directly upon the brilliant 

 blua and crimson hues, and then, suddenly regaining its 

 ordinary position, it will spread all its fins to their utmost 

 and sail majestically by, giving the spestators the impres- 

 sion of a larger fish than it really is. This is kept up, I 

 think, for several days, and, if not interrupted by the in- 

 trusion of a rival, results in a graceful acceptance. Here 

 I am puzzled, for, as often as I have watched these fish, I 

 never could detect any movement that would warrant me 

 in -interpreting it as a sign of acceptance. Indeed, it is 

 highly probable that they have means of communicating 

 ideas by movements so slight as to escape our closest 

 scrutiny. In the spring of 1873 I noticed one of these 

 river sunfish endeavoring to make a favorable impression 

 upon a female. Whether she paid any attention to the 

 nervously active gallant, I can not tell ; I only know that 

 she remained stationary for hours, while the male passed 

 up and down, and from side to side, almost as steadily as 

 clock-work. If disturbed, away they both would dart, 

 but only to return in a few moments, each to resume its 



