174 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



increases again toward midsummer. After midsummer 

 they become less abundant, but during the autumn and 

 early winter they increase again. That is to say, that 

 except for the increase towards midsummer, which is 

 characteristic for both grounds, and is largely due to the 

 appearance of fish of that same year's spawning, their 

 distribution on the two areas is to some extent comple- 

 mentary. The general conclusion is confirmed by the 

 study of the figures for the separate years (as far as these 

 go). This curious behaviour of the same fish on two 

 adjacent areas is perhaps to be explained by supposing 

 that migration from the one area to the other takes place 

 during the spring and autumn. What the causes of such 

 migration may be we are not in a position to say. The 

 migrating fish are largely those of that same year's 

 spawning. 



It might be expected that the distribution of dabs 

 would follow closely that of plaice. It will be seen that 

 the curve of distribution (III.) on Area A is very similar 

 to that for plaice. The minimum for both fishes occurs 

 at the beginning or end of the year, but the maximum 

 catch was taken earlier in the year in the case of the dab. 

 In the three years, 1893, 4, and 5, for which the data 

 are most complete, the maximum catches of dabs were 

 made earlier than those of plaice. As in the case of 

 whiting the curve shows two maxima which have the same 

 positions. 



The distribution of dabs on Area B is not exactly 

 similar to that of plaice, but seems to be rather irregular. 

 It is, however, the case that large catches were made there 

 at the beginning and end of the year. The catches made 

 about the middle of the year are, however, somewhat 

 irregular. 



