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To facilitate the matter I have prepared the Chart, Plate XI, which shows the 

 distribution in the sea of the eel fry undoubtedly in Stage 5. I have included all the 

 references I could find in the literature which from the descriptions (lack of colour, length, 

 mode of life) could be considered as Stage 5, but have omitted the cases where there 

 might be some doubt as to whether they really belonged to this stage'. Further, I have 

 myself investigated most of the specimens for which the place of capture is noted on 

 the Charts 



It must first be mentioned, that the colourless Stage 5, during which the eel fry still 

 lead a completely or partially pelagic life, is restricted in occurrence mainly to the winter 

 half-year, and the Chart showing its distribution supplements therefore the Chart Plate X 

 which shows the distribution of Stage l {Lpptocephahis brevirostris), as we thus obtain 

 a picture of the distribution throughout the whole year of the youngest known stages of 

 the eel. As will be seen from the explanations; I have used various signs according as 

 the specimens were taken in October— December, January— February, March or April. 



A study of the Chart shows that specimens were found to the west of Ire- 

 land even in October— December, namely in November, on the coast of England 

 not before January and on the coast of Denmark not before March (beginning 

 of this month). Even if the Chart only gives a very imperfect picture of the distribution, 

 owing to the incompleteness of the existing records, it shows nevertheless quite clearly 

 without any doubt, that the glass-eels appear earlier further to the west (round 

 Great Britain) than further to the east within the region where this stage 

 chiefly occurs. Attention may be specially called to the two takes of glass-eels in the 

 Atlantic west of Ireland in November; they are very important and interesting. It also 

 appears from the Chart that Stage 5 has never been found in the true Baltic, but 

 on the other hand as far away from the European coasts as Iceland, where I myself have 

 taken pelagic specimens in April. 



I may now proceed to the consideration of the period at which the elvers appear on 

 the different coasts. In all the authors who have in any way dealt with the subject the 

 view is found, that the ascent of the eels takes place earlier in the year in the southern 

 than in the northern regions, thus in general that it is earlier in South than in North 

 Europe. But no intelligible explanation of this phenomenon is to be found in the literature. 



In any case it is not at all easy to compare the available data with regard to the 

 period when the elvers appear, as they may indeed run up during most months of the 

 year, and both the younger and the older individuals. Further the same interest has 

 by no means been devoted to the phenomenon everywhere, and there is thus no doubt 

 that the ascent at several places from which data are available in reality takes place 

 earlier in the year than is noted. In such cases a chance specimen or two may have 

 been observed without any notice having been taken of the earlier. 



1 In a few cases I have included specimens, though the descriptions did not show with certainty that they 

 belonged to Stage 5, because they were found pelagically, which is a sufficient guarantee that they were in 

 Stage 5. See further notes on the catches marked on the Chart. 



2 It should be mentioned that I have included all certain references (without any attempt at choice), for 

 which reason it is probable that the Chart gives in the main a correct picture of the actual conditions. It 

 should further be mentioned that the great majority of the data are for the year 1904: 



