— 161 — .TOHS. S(mMTl)T 



This applies for examplo (,o tho. haddook and oven to a groai.er extent; perhaps to the torsic 

 and blue ling, and espei^ially iiowevor to the Poutassou (see Special Part regarding these 

 species); of the last-named indeed, which only spawns in the Atlantic, numerous larger 

 specimens have been found far north in the Norwegian Sea up to 70° N. L. (see p. 151). 



Concerning the direction of the currents on the British coasts there does not seem to 

 be complete agreement amongst hydrographers. That there is a movement from south to 

 north along the west coasts of Scotland and Ireland seems, however, to be generally 

 admitted. On the other hand I must mention that a current bottle thrown out by the 

 "Thor" on May 29th 1908 near the Rockall Bank (Stat. 14, 57°09'N., 13° 16'W.) landed near 

 Malin Head, North coast of Ireland (found there on August 12th, 1908). Thus this bottle 

 had moved mainly in a south-easterly direction and the same was the case with another 

 bottle, which was found on July 25th, 1908 at Achill Island Co. Mayo, Ireland. 



With regard to the Irish Sea, where the conditions seem on the whole very compli- 

 cated and variable, some hydrographers have stated recently that the current goes north- 

 wards from this along the west coast of Scotland \ whilst others state that water is car- 

 ried from it towards the south to the English Channel^. On the basis of the "Thor's" 

 investigations I.N.Nielsen has shown ä, that the temperatures over the coastal shallows 

 south of Ireland are relatively low (lower for example than off the Hebrides) "although 

 there are much warmer masses of water toward the south and west". He concludes from 

 this "that the current over the coast shallow S. of Ireland flows slowly in comparison 

 with the speed of the current W. of Ireland or even that the current perhaps does not 

 flow in an eastern direction". On the basis of his and Matthews' work, he seems to think 

 it probable indeed that there "all round Ireland flows a current in an anticyclonic direc- 

 tion", that is, from the Irish Sea to the south and thence to the west and north coasts, 

 or something similar to what has been shown to happen at Iceland and on the coast of 

 Scotland where the west coast current going northwards bends round the north coast and 

 continues in a southerly direction along the east coast*''. 



enormous distances (cf. the discovery of the Leptocephalus of the conger in the neighbourhood of Chri- 

 stianssund in Norway and of the quite young transparent elvers (of Anguilla) in the neighbourhood of 

 Bodo ca. 67° N. L. in Northern Norway, as has already been described in my paper ; Contributions to the 

 life-history of the Eel: Rapports et Procès- Verbaux, vol. V, 1906, p. 190 and 214). 



In contrast to these species with long duration of the pelagic stage, others amongst the gadoids 

 may also be named in which this stage seems to be only of very short duration, e.g. bib (G. litscus), to 

 some extent also pollack {G. pollachius), but nothing in our investigations indicates that any great trans- 

 port of the pelagic stages of these takes place. 



' Martin Knudsen : Publications de circonstance, No. 39, 1907, p. 3. 



2 Donald J. Matthews: Mar. Biol. Assoc. Report I, 1902—3, London 190.5. 



= I. N. Nielsen: Meddel. Kom. Havundersog. , Serie Hydrografi, Bind I, No. 9, Copenhagen, 

 1907, p. 22. 



* I shall not enter further here into the discussion of these conditions, concerning which my own 

 investigations do not permit of an independent judgment. It may just be remarked, however, that the 

 existence of an anticyclonic current round Ireland, i. e. from the Irish Sea (where the winter and spring 

 temperatures and salinities are much lower than for example on the south and west coasts of Ireland, 

 e. g. going down even below 6°— 7°), would make the relatively great abundance of the pelagic fry of 

 the species of the northern group on the south-west coasts more compreliensible to me. 



21 



