GENERAL OUTLINES OF ICHTHYOLOGY. 33 



legs'i and by means of the former several of the spiny- 

 finned species are enabled to progress upon dry land, and 

 even to travel considerable distances from one pool to 

 another*. The pectorals are supported by two bones 

 behind the gills, one on each side, which are sometimes 

 imbedded in the muscles, and sometimes connected with 

 the spine, but more generally attached to the bones of the 

 head. 



The ventrals are commonly attached to the sides of the 

 belly. 



Teeth. 



Closely connected with the fins and gills, as furnishing 

 marks by which the subgenera of Fishes may frequently be 

 distinguished, are the Teeth, which are so permanent in 

 their characters as to be well worthy of particular atten- 

 tion. The teeth in various species differ materially in 

 situation, number, and form : many species are almost, if 

 not wholly, toothless ; whilst others possess them on all the 

 bones which assist in forming the cavity of the mouth and 

 throat. They are found on the inter -maxillaries, the max- 

 illaries, the lower jaw, the vomer, the palate, the tongue, 

 the gill-arches, and even on the bones of the throat, or 

 pharynx, behind these. This latter is particularly the case 

 in the herbivorous fishes. 



Sometimes the teeth are uniform in shape on the various 

 bones of a single mouth ; in other cases they are of dif- 

 ferent patterns. The most usual form in carnivorous 



* An account of these fishes will be found in the Chapter on Pike. 



c5 



