PISCES FISHES. 511 



enjoying any very refined sense of taste. Those species which are 

 carnivorous are of necessity compelled to catch with their mouths, 

 and retain a firm hold of the active and slippery food they are 

 destined to devour : to divide or masticate their aliment would be 

 impracticable ; and, even were they permitted so to do, the water 

 which perpetually washes over the interior of their mouths would 

 obviously preclude the possibility of appreciating savours. In the 

 construction of the mouth of a fish we therefore find, generally 

 speaking, that every part has been made subservient to prehen- 

 sion : teeth, sometimes in the form of delicate spines, or else pre- 

 senting the appearance of sharp recurved hooks, have been fixed 

 in every possible situation where they could be made available as 

 prehensile organs ; not only are the jaws densely studded with these 

 penetrating points, but they are occasionally placed on every bone 

 which surrounds the oral cavity, or supports the entrance of the 

 pharynx. The intermaxillary, the maxillary, and the palatine 

 bones, the vomer, the branchial arches, the pharyngeal bones, and 

 even the tongue itself, may all support a dental apparatus, either of 

 the same description or composed of teeth of different shapes ; 

 generally, however, some of these bones are unarmed, and occa- 

 sionally teeth of any kind are altogether wanting. 



But if such is the most usual arrangement of the dental appa- 

 ratus in fishes, we must be prepared to find, in a class so extensive 

 as that we are now investigating, various modifications both in the 

 form and arrangement of the teeth, adapting them to the diverse 

 habits and necessities of individual species ; and a few of these we 

 must not omit to notice in this place. 



The Myxine, or Hag-fish, one of the lowest of the entire class, 

 possesses no osseous framework whereunto teeth could be attached ; 

 and yet, from the parasitical life which this creature leads, it has 

 need of dental organs of considerable efficiency. The Myxine, 

 feeble and helpless as the casual observer might suppose it, is in 

 reality one of the most formidable assailants with which the larger 

 fishes have to contend, since neither strength nor activity avail 

 aught in defending them against a foe apparently so despicable : 

 fixing its mouth firmly to the skin of its comparatively gigantic 

 victim, the Myxine bores its way into its flesh by means of a dental 

 apparatus of a very extraordinary description. A single fang-like 

 tooth is fixed to the median line of the palate, and the tongue is 

 armed on each side with two horny plates deeply serrated : thus 

 provided, the Myxine, when it attacks its prey, plunges its palatine 



