— 132 — 



eratures of the same date in the North Sea. This can be seen from all the international 

 Bulletins for the winter and spring months and is also obvious from the Charts fig. 11 

 p. 137 and figs. 9 and 10. We see from these that the bottom temperature in Feb. — March 

 1906 was greater than 9° in the most western part of the Channel and higher than 8° 

 in the greater part of the region. 



Eeferring to the surface temperatures given in the table p. 115 for Plymouth I may 

 here summarise the English observations (1906) published in the Bulletin, which were 

 taken at 3 stations in the Channel, lying partly in the western (1), partly in the central (2) 

 and partly in the most eastern parts (3). 



Temperatures in 1906 

 in the most western, central and most eastern parts of the Channel 



' The November observations were made at the near-lying Belgian station B.U (SO'Sg'N., 1°27'E; depth 58 meters). 



We see from these figures that there is practically no difference in temperature be- 

 tween surface and bottom, except in the summer; further, that in winter and spring (thus 

 during the spawning time of the gadoids) the temperature decreases evenly from west to 

 east (cf. Chart fig. 11 p. 137) and lastly, that the yearly fluctuations on the other hand in- 

 crease evenly from west to east which is in agreement with the fact that we are thus 

 going further and further away from the influence of the Atlantic water. 



From the Bulletins and the Charts figs. 9 — 10, we find (hat the salinity also decreases 

 evenly from west to east, at least in winter and spring. Kelatively high salinities 

 (ca. 35-30 "/go or even more) occur especially in the western and central parts, but in the 

 belt quite close to the coasts they are naturally lower. 



With regard to the production of the gadoid fry the English Channel has a charac- 

 teristic position, due partly to the shallowness of this region, partly to the relatively high 

 temperatures and salinities occurring at the spawning time. The species which are spec- 

 ially characteristic for the Channel, in that they spawn in quantities there, are the bib 

 {G.luscus), pollack {G. pollachius) and poor cod (G.minutus). Large quantities of the 

 whiting [G . merlangus) are likewise produced. Not less characteristic is the fact that the 

 production of all the other of our gadoids is either inconsiderable or quite nil^ 



' It is also certain that the hake (Merlwccius vulgaris) also spawns in the western part of the 

 Channel, but I cannot say vnt\i certainty whether the production is anyway large (cf. p. 97). 



