FISHES 1343 



the place of the lost members. Any one may gain a 

 good idea of the formidable array of teeth in fishes, 

 and of the manner in which one set succeeds another, 

 by inspecting the jaws of a shark in a museum. In 

 fishes the teeth are not implanted in sockets, but are 

 fastened by ligaments to the surface of the bones 

 which bear them. Sometimes one tooth only is de- 

 veloped in fishes. This is the case in the curious, 

 eel-like hag-fishes already mentioned; these fishes 

 possessing but a single large tooth, borne on the 

 palate; and by means of this formidable weapon, 

 which possesses saw-like edges, they bore their way 

 into the bodies of other fishes, and there take up their 

 abode as unwelcome guests. A cod or large haddock 

 may sometimes be found with five or six hags con- 

 tained in its interior. The parrot-fishes, or Scari, of 

 tropical seas, are so named from their possessing jaws 

 shaped like the beaks of those familiar birds, and 

 these jaws are rendered all the more extraordinary 

 from their being covered or incrusted by numerous 

 small teeth, which are as closely packed on the jaw 

 as paving-stones are in a street, and which serve 

 these fishes as useful instruments when they feed 

 upon the living parts of the hard and limy coral- 

 animals. In the jaws and floor of the mouth of the 

 Port Jackson shark, or in the Eagle rays, or skates, 

 the teeth may be seen to be flat and broad. Such 

 teeth form a regular pavement arranged like a mo- 

 saic pattern, and are admirably adapted for crushing 

 whatever substances enter the mouth. 



Fishes are well provided in the way of digestive 

 apparatus. A throat or gullet, stomach, intestines, 



