FISHES 159 



Schmidt conclusively traced the Eels' breeding grounds 

 to a region of the West Atlantic south-east of Bermuda, 

 where the water is 3,000 fathoms or more deep. On hatch- 

 ing the infant Eel in no wise resembles the form of its 

 parents, being flat, leaf-shaped and transparent. When 

 a few months old these tiny creatures leave their birthplace 

 and, ascending towards the surface where they meet the 

 eastern currents, are swept along towards European 

 shores. For three years they travel slowly onwards, mov- 

 ing four or five miles a day in a journey eventually covering 

 about 3,000 miles. It is not until the third year, when 

 they measure about three inches in length, that they begin 

 to alter in appearance and become round-bodied fish. 

 They are then known as Glass Eels or Elvers. Their 

 journey by sea completed, the invading hosts of Elvers 

 make their way inland, ascending rivers and streams 

 undeterred by any obstacle however formidable. They 

 scale lock gates, wriggle up the boulders beside waterfalls, 

 and sometimes even travel overland when the ground is 

 damp. Eventually they find their way to those ponds, 

 ditches and lakes which must constitute a haven of peace 

 after their prolonged travels. Here they setde for from 

 five to eight years, when the mysterious call of the sea 

 summons them back to their birthplace. They then once 

 more set out on their stupendous journey through fresh- 

 water and salt to the depths of the Atlantic from whence 

 they came. Their return, however, is the completion 

 of their life cycle, for after spawning death ensues and 

 another multitude of larval Eels are setting out on their 

 tremendous journey. 



The breeding ground of the nearly related American 



