184 THE STORY OF FISH LIFE. 



known, and wifch this knowledge came a revela- 

 tion as to its great importance from a pedigree- 

 making point of view. The bow-fin is a carni- 

 vorous fish. The streams in which it lives 

 frequently become very foul ; on such occasions 

 it comes to the surface to breathe air, taking in 

 large mouthfuls at the surface without making a 

 single bubble. It is said that when near to the 

 surface the bow-fin often gives vent to a bell-like 

 note, which is explained as probably due to the 

 passage of air from the air-bladder. This last 

 is cellular in structure, and hence adapted for 

 breathing purposes. 



Once upon a time the distribution of the bow- 

 fin over the earth's surface was much wider than 

 at present, for its fossil remains have been found 

 in the Upper Eocene of Hampshire and the Isle 

 of Wight, and of Paris. But we can trace it 

 much further back than this, for under another 

 generic name — Megalurus — it occurs as far back 

 as the Kimmeridgian formations of Bavaria, that 

 is to say, it is a Jurassic fish, and that is a long 

 while ago ! But we can trace them yet further 

 back, for the Amiidce^ the family to which the 

 bow-fin belongs, were preceded by, and descended 

 from, a group of fishes known scientifically as the 

 Eugnathidce, occurring in the Lias formations at 

 the bottom of the Jurassic series. One of the 

 chief points of difference between these and the 

 modern bow-fin was the possession of a coat of 

 armour in the shape of a heavy pavement -like 

 scale. 



A branch of the bow-fin family, which ranges 

 throughout the Jurassic and Cretaceous periods, 



