CHAPTER IV 



Framework 



THAT the trout and the tarpon are considered by the ich- 

 thyologist low forms of fish is a shock to the sportsman, 

 who looks upon them as among God's fairest creations. It 

 must hastily be added that the ichthyologist's opinion is in 

 no way derogatory. He bases his judgment on the structure 

 of the animal, not on its mode of life nor its fighting ability 

 nor its food value. He uses the words "low" and "primitive" 

 to denote similarity to a generalized ancestral type. The 

 trout and the tarpon, with their symmetrical bodies and their 

 widely spaced paired fins, have diverged less than most liv- 

 ing fish from the creatures which are thought to have been 

 the common ancestors of most present-day fish and of all the 

 higher land animals. 



SKELETON 



The essential elements of the fish framework are a skull, 

 a backbone made up of a series of vertebrae, and two pairs of 

 fins: the pectorals, and the pel vies or ventrals. Allow for the 

 transformation of these paired fins into limbs, and they are 

 the same elements which are found throughout the verte- 

 brates. In addition, the fish skeleton has some features which 

 are either omitted or modified in the higher animals. It has, 

 along the mid-line of the body, one or more dorsal fins on 

 the back and one or more anal fins on the under side, made 

 up of bony or cartilaginous elements unattached to the rest 

 of the skeleton. It has a caudal, or tail, fin, firmly attached 



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