NATURAL HISTORY. 349 



Had I like fish, with fins and gills, been made, 



Then might I in your element have play'd ; 



With ease have dived beneath your azure tide." FA 



MISCELLANEOUS. 



1132. How is the breathing of fishes conducted? 



The breathing of fishes takes place by gills. The water, 

 which is impregnated by atmospheric air, is taken in by the mouth, 

 and forced out again by the apertures on each side of the neck. 

 It is thus made to pass between the gills, which form a set of 

 comb-like vascular fringes, supported upon a system of bones 

 termed the branchical arches, and during this passage the air is 

 absorbed by the blood of the fish. 



These fringes are generally four in number on each side, and 

 are attached by one extremity to an intermediate chain of bones 

 situated opposite the middle of the neck, behind the hyoid bone, 

 while by their opposite extremity they are joined by ligaments to 

 the under surface of the skull. 



1133. fl% is the flesh of fishes white? 



Because the oxidized blood is chiefly confined to a few internal 

 organs, as the heart, liver, kidneys, lungs, and gills ; the flesh 

 is consequently white and apparently bloodless. 



1134. Why do fishes swallow their food hastily, and without 

 mastication ? 



Because they are obliged unceasingly to open and close the 

 jaws for the purpose of respiration, and cannot long retain food 

 in the mouth when quite shut. 



1135. Why are the teeth of fishes slightly curved inwards ? 

 Because this form is best adapted for taking a firm hokl of 



prey, which is frequently alive, and which without such a pro- 

 vision would, in its struggles, easily escape from the mouth of 

 the captor. 



1136. Wl,y does a fish gasp violently when taken out of 

 the water ? 



Because it endeavours to separate the gill filaments, by which 



