AMERICAN INSTITUTE. 44l 



The mouth of the sturgeon is a complete force-pump, and is 

 constantly employed driving water through the fringes of the gills 

 with great force. The mouth of the lizzard, frog and toad may 

 be called a bellows, by means of whicji the animal forces air into 

 its lungs, which are composed of long, narrow cylinders, extend- 

 ing from one end of their bodies to the other; they may be killed 

 in a few minutes by fastening their mouths open, when they die 

 for want of air. All animals that breathe atmospheric air have 

 two hearts, united, called a double heart, one of which throws 

 all the blood into the lungs, and the other forces it through all 

 the arteries in the body; both are force-pumps, and both have 

 valves. Fish are cold-blooded, and have but one heart of the 

 gills, which answers the same purpose as the heart of the lungs 

 in animals. Whales are warm-blooded, breathe air, and are, 

 therefore, supplied with a heart and lungs, but no gills; conse- 

 quently, a whale is not a fish. A fish cannot breathe air or water 

 alone; they must be mixed, and therefor it would seem to follow 

 that a fish is not an animal. 



The digestive apparatus of the sturgeon is simple and complete, 

 and is capable of secreting gastric juice very rapidly, and in great 

 abundance. To prove this, I killed one five hours after he had 

 swallowed a frog, but there was nothing remaining of it in his 

 stomach except two small bones. 



Surprise has been expressed by gentlemen, that I could fresh- 

 waterize salt-water fish. Now, the fact probaby is that all fish 

 were originally salt-water fish, and inhabitants of the ocean; but 

 the Deity having implanted in them habits of wandering, they 

 have been gradually dispersed thoughout all the waters tributary 

 to the great ocean, and carried by birds to every pond, lake and 

 pool on the face of the earth, which teemed with countless thou- 

 sands of organized insects, eternally propagating their species to 

 supply them with food. Man, animals and fish can, at all times, 

 change their residence, and soon become acclimated to any 

 locality. 



The Salmon {Salmo 5'a/ar).— The upper part of the female is some- 

 what larger than the under, and in the male fish the under jaw 

 curves up, so that the sexes may be easily distinguished by this 



