— 261 — 



Stages in ücvclopment (scc Chart, PI. X). ün the contrary, vvc sec that Stage ,"> is found 

 in the English Channel, North Sea, Skager Rak and Kattegat as well as in the 

 waters off Norway and Iceland. (2) That the elvers (Stage 5) appear earlier in the 

 waters off the coasts of Great Britain, where they are already found from November on, than 

 further to the east in the Danish waters, where they have not hitherto been found earlier 

 than the beginning of March. (3) That the elvers in Stage 5 are certainly not found 

 in the Baltic, where however older eel fry occur, though on the other hand they are 

 found as far north as Iceland where but few eels live. All this is in agreement with the 

 fact discovered by the -'Thor", that the spawning places of the eel are in the Atlantic 

 west of the British Isles and France. 



By means of the various reports from the coasts of West and North Europe, we 

 are further enabled to follow the eel young on their way from the spawning places in 

 the Atlantic to the places where they will pass their future life. Reports regarding the 

 ascent of tiny eel fry on the European continent are to hand right from the southwest 

 of Spain northwards to Denmark, the west coasts of Sweden and Norway at least up to 

 67° — 68° N. L. and further from the Atlantic Islands (Great Britain, Faeroes, Iceland). 



Several important conclusions can be drawn from these reports. For example we 

 find, that far greater quantities of tiny elvers occur on the true Atlantic 

 coasts than on those further from the Atlantic. This is already seen in an 

 indirect way from the fact that a characteristic and at certain places extensive fishery 

 for the tiny elvers (in Stage 5) with the use of them as food has been able to develop 

 on the true Atlantic coasts (Spain, France, South West England, partly also Ireland), but 

 only there. The fishery attains a great importance especially at those places which lie 

 in the neighbourhood of large spawning places for the eel (e. g. along the coasts of the 

 Bay of Biscay), or on coasts which in consequence of their whole form and direction 

 come to play the part of a fishing apparatus for the elvers migrating inwards from the 

 sea (e. g. Bristol Channel in South West England). 



A direct comparison of the condifions on the different coasts of West and North 

 Europe shows further, that the elvers decrease in quantity from west (West 

 Coasts of Great Britain and France) to east (North Sea, Kattegat, Baltic). 



It appears also from the reports that the time of occurrence of the elvers on the 

 different coasts depends in the first place on the distance from the deep water in 

 the Atlantic where the eel spawns (cf. Chart, Pi. XII). We thus see that the ascent 

 is observed earliest on the coasts of Spain, South West France and Ireland, from which 

 the distances out to the 1000-meters line are quite short. The geographical height of the 

 place has only a secondary importance, in this way namely, that the elvers sometimes, 

 especially in colder regions, remain in the sea at the coasts and only begin to run up 

 into the fresh water in great quantities, when the temperature of the latter becomes higher. 



On the coasts directly washed by the Atlantic Ocean, the ascent of the 

 elvers of the 1st year's group into the fresh water begins already in September- 

 December, January and February, all according to the distances from the deep 

 water. So far north in the Atlantic as at Iceland however, the ascent has not been 

 observed before the end of March. 



