NATURAL HISTORY OF AMIA CALVA LINNAEUS. 85 



centimetres of the nest and then slowly backed away to a distance of about 4 metres 

 and lay quiet with his tail toward the nest. Presently the first male left the nest, 

 went rapidly to the second fish, appeared to bite him in the side, and drove him 

 away. I have never seen the fierce battles described by Whitman and Eycleshymer, 

 but I do not doubt their occurrence. Males are sometimes found with fresh wounds 

 on the head or with the tail partly torn away. These wounds I at first supposed 

 were due to the battles of the males, but in subsequent seasons when I had so 

 arranged it that no Amias were speared on the spawning grounds, I found no more 

 such wounded fish. 



Besides guarding the nests against their own kind the males keep off minnows, 

 sunfish, and probably other small fish that feed on the eggs. There is no surer 

 sign of an abandoned nest than to find it occupied by small fish. I have also found 

 turtles and tadpoles in such nests, but this is possibly accidental. 



As the male guards the eggs one is struck by certain resemblances between 

 his colors and those of surrounding objects. All his fins are of a green like that of 

 the aquatic vegetation and blend with it readily. The reticular markings on his 

 sides bear a close resemblance to the shadows cast by the intercrossing leaves of the 

 vegetation floating at or near the surface. This resemblance is so close that after 

 prolonged examination at a distance of a foot or two I have been unable to say 

 with certainty which of the reticulations on the side of the male were due to pigment 

 and which were shadows. They could only be distinguished through some slight 

 movement of the fish. Moreover, the tail-spot bears a striking resemblance to 

 certain refraction images that are commonly seen on the bottom in shallow water. 

 These are seen on sunny days wherever minute elevations of the water surface are 

 produced by the projecting tips of water plants. They are of about the size and 

 form of the tail-spots of the male Amia; the colors are the same; the relative width 

 of border and central area is the same; the color of the background on which they 

 are projected is the same. As one looks from one to the other, the likeness, once 

 seen, is remarkable. Besides this, the general brown-green or bronze-green color 

 of the back and sides of the male blends with the brown tone of the pond bottom. 



I do not know that the male is less conspicuous than the female when the two 

 are together on the spawning ground, for they are not seen together except when 

 spawning, and the observer is then occupied with other matters. This could be 

 determined by examining recently killed fish side by side in their natural surround- 

 ings. Of this much, however, I feel sure, that given the colors of the male it would 

 be difficult to produce a natural color pattern that would render the fish less con- 

 spicuous than that which he possesses. Before the extermination of fishing mam- 



