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. . 1 , i i : i i : ; FISH SHED AND RENEW THEIR TEETH Edward ONell is correct in saying that muskel-lunge do not shed their teetli to such an extent that they are toothless; but they, like most other fish, do shed teeth. There are a few fish, such as the puffer, or "swell-toad," and the ocean sunfish, which have horny plates instead of teeth, which probably do not shed them, but practically all others, even the minnows and suckers, shed their teeth as they get worn out and grow new ones. It is likely that Mr. Mould was deceived by the fact that the muskellunge has what are known as "hinge teeth." He may have been able to pull out one or two which were ready to fall away and found that he could push the others back readily with his finger, but if something had happened to startle him when his finger was just past the point of a tooth he might have found that when that tooth had straightened up to a certain point it was his finger that gave the rest of the way. If one will cut up the jawbone of a muskellunge or a great northern pike he will find under the skin and in the bone many new teeth in different stages of growth. As the old teetli get worn down or torn out the new ones grow in to take their places. This never takes place all at once, but all the teeth in the mouth of an old pike or muskellunge have been renewed many times. In some of the sharks there is an interesting arrangement for renewing the teeth. In the great "man-eaters" there is a single row of cutting teeth standing on edge along the jaw, but behind each tooth is a row of others, one fully developed, the next almost grown, the next a little smaller, and so on down to some that are only little buds with a hard point. These teoth lie flat and are held by the skin of the pocket where they grow. When one of the cutting teetli is torn off, worn out or broken, the perfect one next to it springs right up and grows fast so that in a day or two I the row is as good as ever. In the sharks with several rows of teeth in the jaws the new teeth are formed" at the back of the jaw inside the mouth and move up over the jaw until they are finally worn out and drop off after they have traveled outside of the mouth. Most persons think that the carp our largest minnow and the suckers have no teeth, but down in their throat, behind the last pair of glls, is a pair of sickle-shaped bones with teeth which work against a thick, hard pad above them. Many other fishes have a similar arrangement of teeth in the throat pharyngeal teeth, the scientists call them. In the big "black drum" of the Atlantic Coast this pair of bones is grown together and covered with blunt, round teeth which make a pavement sometimes as large as a childs hand. This bone Is often sent to museums by persons who want to know what H U. In one case a few years ago a man wrote that he had a bone with pearls on it Avhich he wanted to know about. He also told how much he had been offered for it and indicated that he would sell It to the museum if offered enough. The picture he sent showed what It was, and it was necessary to tell him that he could probably get several dozen like it at the nearest fish market. There is much more that might be said of fish teeth, teeth broad and flat as a paving block, round as a cobble, sharp as a knife, long and slender as a needle, teeth on hinges, teeth solidly set in the bone of the jaw, teeth for cutting, holding, grinding or tearing. Alfred C. Weed In Field and Stream.
