
806 THE AMERICAN NATURALIST. | [Vor. XXXVI. 
At the same time other markings are intensified, and in many 
species the head and sometimes the body and fins are covered 
with warty excrescences. These shades are most distinct on 
the most vigorous males, and disappear with the warty excres- 
cences after the fertilization of the eggs. 
Nuptial colors do not appear among marine fishes, and in but 
few families are the sexes distinguishable by differences in 
coloration. 
Recognition Marks. — Under the head of “recognition marks” 
may be grouped a great variety of special markings, which may 
be conceived to aid the representatives of a given species to 
recognize each other. That they actually serve this purpose is 
a matter of theory, but the theory is plausible, and these mark- 
ings have much in common with the white tail feathers, scarlet 
crests, colored wing patches, and other markings regarded as 
recognition marks among birds. 
Among these are ocelli, black or blue ringed with white or 
yellow, on various parts of the body ; black spots on the dorsal 
fin; black spots below or behind the eye; black, red, blue, or 
yellow spots variously placed; crossbars of red or black or 
green, with or without pale edges; a blood-red fin among pale 
ones or a fin of shining blue; a white edge to the tail ; a yellow, 
blue, or red streamer to the dorsal fin, a black tip to the pec- 
toral or ventral; a hidden spot of emerald in the mouth or in 
the axil ; an almost endless variety of sharply defined markings, 
not directly protective, which serve as recognition marks, if not 
to the fish itself, certainly to the naturalist who studies it. 
These marks shade off into an equally great variety for which 
we can devise no better name than “ornamentation.” Some 
fishes are simply covered with brilliant spots or bars or reticu- 
lations, their nature and variety baffling description, while no 
useful purpose seems to be served by them, unless we stretch 
still more widely the convenient theory of recognition marks. 
In many cases the markings change with age, certain bands, 
stripes, or ocelli being characteristic of the young and gradu- 
ally disappearing. In such cases the same marks will be found 
permanent in some related species of less differentiated colora- 
tion. In such cases it is safe to regard them as ancestral. 
