The forms of fishes are very numerous. Some are extremely long and slender, as many of the species of Eels, Pipe-fishes and the like, while others are extremely short, like Sunfish of the ocean. Others, like the Trunk Fishes, are nearly equal in all dimensions. The average form and the one which best suits our idea of a fish, is the Black Bass, or other fishes of similar pattern. To know the advantages of these forms one must study the fishes in their native element. The peculiar forms which many species take are the most noticeable in those found in the tropics. The struggle for existence there is the most severe, and it seems as if each species had labored to take on some peculiar form which would assist most in its preservation. In this respect color also plays an important factor. It is in the tropics and among the many species of corals that we find the most highly-colored fishes. Many fishes have the power to change their color, and this they can do in a very short time. The flounders are a peculiar family, the young when born are symmetrical. Early in life they take on the habit of their parents and lie on one side, the eye on the underside disdains to look downwards and so begins to move toward the other side. The bones of the head suit themselves to this change and soon our flounder has both eyes on the same side of the head. The upper side is colored much to resemble sand, and the under side becomes nearly white. The flounder protects himself by covering his body, except the eyes, with sand. Flounders live on sandy bottoms, some in shallow water, while others are found in deepest parts of the ocean. If flounders are placed in an aquarium and arranged so the light can fall on the under side of their bodies, this, too, becomes dark, much like the other side.