FISHES OF CHESAPEAKE BAY 
113 
I think I am now abls, after so many years’ work, to chart out the spawning places of the European eel. The great center 
seems to be about 27° N. and 60° W. [southwest of Bermuda], a most surprising result, in my opinion. The American eel seems to 
have its spawning places in a zone west and south of the European, but overlapping. The larvae of both species appear to pass 
their first youth together, but when they have reached a length of about 3 centimeters the one species turns to the right, the other 
to the left. 
Neither is it definitely known, as far as the writers are aware, whether the eggs are pelagic or 
at what depth they are laid. The larva; of such sizes as have been taken live at the surface, and it 
is now supposed that the eggs are pelagic. 
The larva, or leptocephalus, is nearly as different in form from the adult as the caterpillar is 
from the butterfly. It was not until about 1895, or approximately 40 years after the leptocephalus 
was first described, that it was definitely determined that the leptocephalus was a young eel. The 
larvae are flat, ribbon shaped, tapering toward both ends. They are transparent, being entirely 
devoid of pigment, except in the eyes, and are readily overlooked in the collecting net. They have 
a well-developed mouth with very large teeth. In the process of metamorphosis the creature loses 
in length and depth but gains in width until the adult stage is attained. 
The growth of the larva; and metamorphosis take place while the young migrate from mid- 
ocean toward the shores. The smallest larvae are taken nearest the spawning ground in mid-ocean 
and larger ones nearer the shores. By the time the eel reaches fresh water a complete metamor- 
phosis has taken place. The length of fully developed larvae, according to Schmidt (1912, p. 8), 
Fig. 68.— Transition stage, 61 millimeters long 
ranges from 60 to 85 millimeters, the length being reduced from 82 to 53 millimeters in the process 
of metamorphosis. The large larval teeth are lost, but they are replaced immediately by perma- 
nent ones. The dorsal and anal fins are produced farther forward; the pigment, however, is still 
largely wanting, as is indicated by the name “glass eel,” and it forms very gradually. The follow- 
ing “ glass eels ” were collected at the surface in Chesapeake Bay by the Fish Hawk and the Albatross . 
