ODD FORMS AMONG FISHES. |
By Professor SANBORN TENNEY.
PROBABLY there is no group of animals—certainly no group of vertebrates—that exhibits more strange and even monstrous forms than fishes.
The typical fish, we may well believe, is some such form as the salmon, or the cod, or the bass, or an average of these and their numerous allies. In a word, the ordinary fishes of the ocean, lakes, and streams, give us essentially the true idea of the typical fish.
But what remarkable departures from these ordinary forms do we
Fig. 1.—Salmon, introduced here as an example of a typical fish.
find when we take a survey of the whole vast group of animals that are called fishes!
Let us take the salmon as a fair sample of an ordinary fish, and then briefly notice a few of the strange forms to which the name is applied.
If we look at the rays (Fig, 2), we see "fishes" whose width is so great in proportion to their length, that in giving their dimensions it would seem to be quite the natural thing to put down the width as the prominent measurement instead of the length, as is our custom in the case of ordinary fishes. And it may be remarked here that the great relative breadth of these animals is connected with the kind of movements which they exhibit in progression. Instead of ordinary swimming, these animals effect locomotion by a sort of flight through the waters; and hence are often called "sea-eagles," "sea-vampires," etc. They all belong to the sea. Some of the rays are of wonderful dimensions, although the ordinary kinds are only about two or three feet wide. One was taken near Messina which weighed half a ton. One taken near Barbadoes is said to have been so large that it required seven yoke of oxen to draw it! Levaillant tells us of one which was thirty feet wide and twenty-five feet long; and Dekay states that one of these monsters of the deep has been known to seize the cable of a small vessel at anchor, and draw it several miles with great velocity!