BREEDING PLACES OF THE EEL SCHMIDT 281 



transformation into the elver. I have not been able, however, to 

 confirm Grassi's theory as to the origin, manner of life, and age, of 

 the larvae. Still, as I have said before, that theory might well appear 

 justified from the state of things at the time it was first advanced. 



The Danish eel investigations were commenced, as mentioned, in 

 1904. I was then on board the research steamer Tkor^ engaged on 

 fishery investigations in the Iceland and Faroe waters, according to 

 the program of the International Council for the Study of the Sea. 

 In May, 1904, after towing a Petersen's young-fish trawl near the 

 surface of the water, west of the Faroes, it was found, on examining 

 the contents of the net, that in addition to various other forms of 

 pelagic life, we had also captured a specimen of Leptocephalus hre- 

 virostris, 71^ cm. long. 



Thus the larva of our eel was for the first time found outside the 

 Mediterranean. And the find, which was followed in the same 

 year by another, made by Mr. Farran from the steamship Helga, off 

 the west coast of Ireland, afforded a starting point for future investi- 

 gations. Owing to various circumstances it came about that Den- 

 mark, a country where eel fishing is a specially important industry, 

 was accorded the task of prosecuting the investigations further, and 

 it fell to my lot to take charge of the work. 



I had little idea at the time of the extraordinary difficulties which 

 the task was to present, both in regard to procuring the most neces- 

 sary observations and in respect of their interpretation. Our work 

 on these eel investigations has now extended some seventeen or 

 eighteen years, with a lengthy interruption occasioned by the recent 

 war. The task was found to grow in extent year by year, to a degree 

 we had never dreamed of ; in fact, we have been obliged, in order to 

 procure the necessary survey material, to make cruises of investiga- 

 tion ranging from America to Egypt, from Iceland to the Cape Verde 

 Islands. And this work has been handicapped throughout by lack 

 of suitable vessels and equipment and by shortage of funds ; indeed, 

 had it not been for the private support afforded from numerous 

 different sources, we should have had to relinquish the task long 

 since. 



I propose now to give a brief survey of the results attained. They 

 are based on dry figures, representing measurements and other obser- 

 vations; yet, taken in conjunction, they give us at least the outline 

 of a life history which in point of interest is, I think, hardly sur« 

 passed by that of any other species in the animal kingdom. 



In 1905, then, systematic investigations into the life history of the 

 eel were included in the Danish program. The researches we have 

 carried out since that date fall into two groups: (1) Investigations 

 at sea; and (2) investigations in the laboratory. 



