The forehead between the eyes consequently becomes, as could be plainly seen, temporarily contracted in breadth.

On one occasion Malm saw a young fish raise and depress the lower eye through an angular distance of about seventy degrees.
We should remember that the skull at this early age is cartilaginous and flexible, so that it readily yields to muscular action.

It is also known with the higher animals, even after early youth, that the skull yields and is altered in shape, if the skin or muscles be permanently contracted through disease or some accident.

With long-eared rabbits, if one ear flops forward and downward, its weight drags forward all the bones of the skull on the same side, of which I have given a figure.
Malm states that the newly-hatched young of perches, salmon, and several other symmetrical fishes, have the habit of occasionally resting on one side at the bottom; and he has observed that they often then strain their lower eyes so as to look upward; and their skulls are thus rendered rather crooked.

These fishes, however, are soon able to hold themselves in a vertical position, and no permanent effect is thus produced.