SYSTEMATIC CATALOGUE OF FISHES. 



109 



at over 10 millions. The female eel is larger than the male, the latter probably 

 rarely exceeding 2 feet in length. The ovaries, two in number, are of a pale 

 yellow color and extend along the vertebral column the, whole length of the 

 abdominal cavity; they are about half an inch wide and are thrown into numerous 

 transverse folds. The two male organs are similarly situated, but have a different 

 shape and appearance; each consists of about 50 lobules arranged in longitu- 

 dinal rows, with a glistening white appearance. The male eel when sexually 

 mature has very large eyes and a short, pointed snout, and its color is silvery 

 gray. 



Fig. 33. Common Eel. AnguUla chrisypa. 



Spawning normally occurs in salt water, in fall and winter. There is some 

 evidence that eels may under exceptional circumstances spawn in fresh water, 

 but it is not conclusive. The migration of the adult eels is said to take place 

 mostly at night, and usually extends to mud banks off the mouths of rivers, the 

 eggs being there laid and fertilized. The maturation of the reproductive organs 

 takes place only after the eels reach salt water, and proceeds rapidly. It is 

 thought by some authorities that all the individuals of both sexes die after once 

 spawning. 



Fig. 34. Leptocephalus of the Common Eel. 



The eggs float at the surface, and are wafted about by wind and wave. They 

 hatch into transparent, much-compressed, lanceolate creatures, with small head, 

 large eyes, and large mouth armed with a few long, sharp teeth; these larval eels 

 are called leptocephali, and are so different in form from the adults that the iden- 

 tification of this stage of the American eel has not been postively accomplished 

 although it is probable that several leptocephali collected by the fishery steamer 

 Albatross in fall about 100 miles off the New Jersey coast and studied by Prof. 



