— 65 — JOHS. SCHMIDT 



the latter occurs in tlie most southerly parts of our region (Bay of Biscay, Channel) , and 

 only G.Esmarki in the most northerly parts (Iceland, Fœroes), whilst on the other hand 

 the two species were found together in samples from the Atlantic coasts of Great Britain. 

 In order to procure accurate information regarding the occurrence of the two species, the 

 very great work was undertaken of counting the vertebrae in all the specimens contained 

 in our samples from the Atlantic coasts of Great Britain, but complete certainty was ob- 

 tained in this way and as mentioned on p. 9 no other certain method exists for the se- 

 paration of the earlier postlarval stages of the two species. 



Both species also occur in the North Sea and the Skager Eak though at different 

 periods, and the counting of the vertebrœ had also to be undertaken here, though not to the 

 same extent as for the Atlantic specimens. Yet the occurrence of the two species is not 

 marked on the Chart, unless all or a large number of the specimens taken at the station 

 concerned were examined for the number of vertebrœ. 



With regard to the depths over which the pelagic fry of Gadus Esmarki occur, a 

 survey of the tables and the Chart of distribution shows that, although it does not belong 

 to the species occurring in very shallow water, yet the great majority of the speci- 

 mens were taken within the 200-meter line. On the other hand but relatively few of 

 the earlier pelagic stages were found over less than 50-meters depths. Beyond the 1000- 

 meter line only 3 specimens in all have been taken amongst many thousands of specimens 

 in the four years, namely, at St. 78, June 1st, 1903, which lies also at a place (on the 

 south-eastern part of Iceland) where the slope of the sea bottom is steep, so that the dis- 

 tance from the 200-meter line is at most 20 miles. Between the 1000 and 200-meter 

 line we have only taken in all ca. 30 specimens in the Atlantic, so that it will be seen 

 that in comparison with the total number very few were found beyond 200 meters. We 

 learn from this that Gadus Esmarki in the Atlantic normally passes through the whole 

 of its pelaglic life within the 200-meter line, and our results with regard to the occurrence 

 of the young bottom stages agree with this. These were not found, like those of the cod, 

 coalfish and pollack, right into the tidal region, but at depths from ca. 50 to ca. 100 meters 

 and in considerable numbers at Iceland in June and July. To judge from the data Gadus 

 Esmarki seems thus to have an intermediate position with regard to the depths at which 

 the fry occur, as it seems to live in the main in depths from ca. 50 to ca. 200 meters. 



With regard to the depth under the surface at which the pelagic fry of G. Esmarki 

 are found, it will be readily seen from the tables that in the hauls close to the surface 

 but very few specimens occur in general. Most were taken deeper down, e. g. with 65 

 meters of wire out, corresponding to about 30 meters. For the rest the tables show that 

 the older postlarval specimens generally occur deeper down in the water than the younger. 



Until quite recently Gadus Esmarki was considered as a very rare and local species, 

 but investigations have now shown this to be incorrect, fieferring for further information 

 to the next section (§ 3) on the geographical distribution, I may here just mention that 

 Fdlton^ has found it in extremely great quantities in the northern North Sea, and that 

 my colleague Dr. A. C. Johanseh on the basis of his numerous fishing experiments with the 

 "Thor" in the Skager Eak considers it to be one of the commonest of the Skager Kak 



1 Fulton, in: 19th Annual Eeport of the Fish. Board for Scotland 1901. p. 282. 



9 



