CHAPTER IV 

 FISHES 



89. What is a fish ? " A fish is a backboned animal which 

 lives in the water and cannot ever live very long anywhere 

 else. Its ancestors have always dwelt in water, and likely 

 its descendants will forever follow their example. So, as the 



FIG. 90. Yellow perch. 



water is a region very different from the fields or the woods, 

 a fish in form and structure must be quite unlike all the 

 beasts and birds that walk or creep or fly above ground, 

 breathing air, and being fitted to live in it. There are a 



120 



