THE FLOUNDER.
But the oddest change of all takes place in the position of the eyes. You can easily see, of course, that if a fish with its eyes in the usual place lies down on one side at the bottom of the sea, one eye is underneath its head, and is quite useless. So you might think that, except when it was swimming, it would only be able to see with one of its eyes. But a very strange thing indeed happens as soon as it lies down on the mud. The lower eye actually begins to move, and slowly travels round the head, till at last it settles down by the side of the other! That sounds impossible, doesn’t it? It is as wonderful as anything in a fairy story. Yet in every one of these so-called “flat” fishes that strange journey of the eye takes place.
Next time you pass by a fishmonger’s shop just look at the soles or the flounders in his window, and you will see that in every one of these fishes the two eyes are quite close together, above the same corner of the mouth. That is because one of the eyes moved right across the head while the fish was quite small, so that it might be able to use them both as it lay at the bottom of the sea.
You can sometimes catch flounders by paddling in the sea in places where the bottom is rather muddy. After a little while you are almost sure to feel one of these fishes wriggling underneath your feet, and all that you have to do is to stoop down and seize it.
PLATE V
THE PLAICE
In its habits the plaice is very much like the flounder, except that it does not like lying upon mud, and always chooses a spot where the bottom of the sea is sandy. And the skin of the upper side of its body, instead of growing dark brown, like the colour of mud, becomes speckled and spotted like the surface of sand. The fish is always very careful indeed to conceal itself, for even when the sea-bottom is sandy it does not lie upon the surface, but wriggles its way right down into the sand, only leaving just its eyes and a small part of its head above it.