— 21 — .ions. SCHMIDT 



and on (ho easternmost, pari of l.he soutli coasir as far as the Horns, where t;hey 

 very suddenly cease.' On tlie east and north coasts on the other liand there are none 

 or practically none in April. Investigation of the temperatures showed that in water 

 below ca. 4° C, but few or no cod eggs were spawned, and in this we have ob- 

 viously the explanation why cod eggs are lacking on the east and north coasts, where 

 the temperature at this time of year is very low (ca. 1° — 3°, see fig. 5, General 

 Part).'' During this first voyage of the "Thor" round Iceland in April 1904, the 

 fishing boats observed were carefully noted and their disposition marked on a chart. 

 It then appeared that their "distribution" agreed exactly Avith that of the cod eggs, i. e. 

 the great majority were working on the south-western part of the land, none on the 

 northern and eastern. There was thus a very good agreement between the conclusions to 

 be drawn from the practical fishery and our biological investigations. In May and June 

 1904 the "Thor" sailed round Iceland a second time. The results so far as the cod is 

 concerned are shown on Chart IX, where the eggs no longer appear but the pelagic young, 

 which are now present in great numbers, in contrast to the condition during the first 

 voyage in April when they were not yet developed. The investigations were renewed on 

 the eastern part of the south coast at the end of May, after which the "Thor" followed 

 the east coast in the last days of May, the north coast in the first days ot June, whilst 

 the west coast was investigated in June. As can be seen from the Chart, the region 

 where the cod young were found was almost the same as in April, as they were absent 

 on the east and north coasts and occurred on the south and west coasts. The relative 

 distribution is however different, the great masses now occurring off the northern part of 

 the west coast. Here enormous quantities of pelagic young cod were now found, having 

 an average length of ca. 1 cm. On the other hand, there were no longer large numbers 

 of cod young to be found on the south-western part of the land, neither pelagically nor in 

 the. bottom stages. 



On considering the distribution of temperature in the waters round Iceland during 

 this second voyage, we find that there was still cold water on the east and north coasts 

 (ca. 1° — 3° in depths of 50 meters, see fig. 6, General Part), and this shows that the 

 limits of the distribution of the young cod lie almost at the 5° curve, namely, in part 

 at Cape North (N. W.) in part at the Horns (S. E.). Thus to the east of Cape North and 

 to the north of the Horns no pelagic young cod were as yet found. 



On the third voyage of the "Thor" round Iceland the conditions had quite changed, 



> Of the two boundaries for the distribution, the north-western and the south-eastern, it is the latter 

 which is the most sharply marked, both for the cod and most of the other species, a condition quite in 

 agreement with the fact that the hydrographical boundary (between Atlantic water and the East Ice- 

 landic Polar water) is here very distinct (see General Part and fig. 5). 



- On the northern part of the west coast the main spawning seems to come somewhat later than 

 on the western part of the south coast (namely in May), and even in the first half of June many eggs 

 of cod were found in the water off the N.W. coast. On the north coast also, especially the western por- 

 tion, some few eggs are spawned in the summer time (thus, some were found at St. 130 and 131 in the 

 beginning of June 1904), and even from the southern part of the east coast I have a single observation 

 which shows, that a few cod eggs may be spawned here in the summer (cf. the quite small specimen 

 6 mm. long found at St. 133 on 27. July 1905). The number of eggs and young produced by this weak 

 "after-spawning" on the north and east coasts, which perhaps stands in connection with the higher summer 

 temperatures, is however quite inappreciable in comparison with the spring spawning on the S. and 

 W. coasts. 



