. British and Irish Salmonidae. Salmon. TEETH AND INTESTINAL TRACT. 21 The teeth in the salmon, trout, and char are of a conical shape and used more for capturing than masti- catiug their prey ^ they are present in both upper (m) and lower (ma) jaws, on the vomer (u), palatine bones (p), and tongue (t). They are frequently shed and as constantly renewed by others. appearing from beneath or else on one side of the dis- carded ones. As age creeps on the number of their teeth become more and more reduced, the teeth-bearing portion of the bones dimin- ish in extent more rapidly in such forms as fr
. British and Irish Salmonidae. Salmon. TEETH AND INTESTINAL TRACT. 21 The teeth in the salmon, trout, and char are of a conical shape and used more for capturing than masti- catiug their prey ^ they are present in both upper (m) and lower (ma) jaws, on the vomer (u), palatine bones (p), and tongue (t). They are frequently shed and as constantly renewed by others. appearing from beneath or else on one side of the dis- carded ones. As age creeps on the number of their teeth become more and more reduced, the teeth-bearing portion of the bones dimin- ish in extent more rapidly in such forms as frequent the sea than those which pass their time in fresh waters. Fig. 9. Diagram of teeth inside mouth of trout: m. maxilla: ma. mandible;^, palatines: t. tongue: v. vomer. The size and arrangement of the vomerine teeth are somewhat varied, as they diminish more or less rapidly in number with certain conditions, especially the character, whether saline or fresh, of the waters in which the fish live. They also vary greatly in different specimens of even the same universally admitted species, from what exists in the earliest period of their lives when they are in a double row, to old age when all may be absent, consequently it would be unsafe to base specific differences upon this dentition. When the tooth-bearing ridge commences to become narrower, the teeth are at first forced into a more or less irregular single line, and subsequently this ridge becomes absorbed commencing from behind and gradually extending forwards and the teeth as a consequence fall out. The teeth in the jaws are comparatively stronger* in fresh-water trout than in salmon or sea trout, as will be subsequently more fully alluded to. The lingual teeth or those on They are shed and renewed similarly the tongue are ia a row of about Jji to the other teeth in the mouth of five or six on either side of the iflRl these fishes, and are more commonly middle line and the largest in the loQi ™ reduced numbers or abs
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