SCALE 01^ AN ADUIvT I^EMAI^E KEL 



The eel was on her way to the sea to spawn when caught in the Potomac River. The 

 age, according to the evidence afforded by the scales, was over eleven years (see page ii44)- 

 Enlarged 25 times. 



HOW THK KEL IS BORN AND WHERE 



The habits of the eel at the time of 

 spawning are entirely unknown. Whether 

 the eggs are laid in deep water, in inter- 

 mediate depths, or at the surface is as 

 yet only a matter of surmise. It is es- 

 tablished, however, that the eggs are de- 

 posited outside of the 1,000-meter curve 

 (that is to say, the eggs are never de- 

 posited in water less than 1,000 meters 

 deep), and that they hatch at or near the 

 surface, where they are carried by their 

 natural buoyancy. 



Up to the present time no eel with 

 ripe eggs has been found, and only one 

 fully mature male has been observed, a 

 specimen 35 centimeters (14 inches) 

 long, recently taken on the coast of Den- 

 mark. 



From counts and estimates based on 

 immature specimens, it is evident that 

 the eels are the most prolific of all fishes 

 and of all backboned creatures. From 

 5,000,000 to 10,000,000 eggs are probably 

 produced by the average-sized eels, and 

 15,000,000 to 20,000,000 must be depos- 

 ited by the largest examples. A speci- 

 men one meter long and weighing 2.6 

 kilograms, taken in the Potomac River 

 in November, 191 2, while migrating to 

 the sea, contained approximately 15,000,- 

 000 eggs from 0.23 to 0.37 millimeter in 

 diameter. 



All large eels are females, and only fe- 



males enter conspicuously into the mar- 

 ket supplies in either America or Europe. 

 Any eel over 40 centimeters (16 inches) 

 long is likely to be a female and one 

 over 45 centimeters (18 inches) is al- 

 most certain to be a female. 



All eels found in the headwaters of 

 large streams are females. The males 

 remain in the lower courses of rivers 

 and as a rule do not go above tidewater. 

 One of the most surprising facts in the 

 eel's life is that all individuals of both 

 sexes die after spawning once. No 

 ''spent" eels have ever been found; no 

 mature ones have ever been seen com- 

 ing in from the sea, and, as a matter of 

 fact, i;io , provision is made by nature for 

 the return to the fresh waters of any of 

 the myriads of eels that go down to the 

 sea each year to spawn. 



Just what becomes of the eels after 

 spawning is not known. The conger eel, 

 a strictly marine species, undergoes a 

 general degeneration or jellification of 

 its tissues after the spawning act, and it 

 is supposed that the common eel meets 

 with the same fate. The writer once 

 had served to him at an inn on the east 

 coast of Japan a common eel that was 

 peculiar in having a gelatinous consist- 

 ency throughout. The specimen had 

 been brought in by fishermen operating 

 offshore in deep water, and may have 

 been a spent fish in process of disinte- 



1143 



