of the, Fishery Board for Scotland. 



287 



herring of the Firth of Clyde remained there permanently, coming out of 

 the deep holes to spawn on the flatter, shallower grounds, so Dr. Heincke 

 considers that the herring never go very far away from their spawning 

 places. 



A number of reasons to support this view will suggest themselves to 

 those who understand the significance of the race-divisions, and we may be 

 content with the position of Dr. Heincke. These are the facts, let those 

 who uphold the extensive migration theory contradict or explain them away. 



There is, however, the appearance of the summer- and autumn -herring 

 on the east coasts of Scotland and England which has always seemed to 

 lend countenance to the migration theory. As is known, the summer 

 herring fishing begins in the North near the Shetland Islands in May or 

 June, then it gradually spreads along the coast in usually a southerly 

 direction, so that off Peterhead the fishing is towards the end of June, 

 further south in August, and so on until the Dogger Bank is reached and 

 there is a break. This is the case with the herring fishing, but it is not 

 necessary to believe that the herring shoal or shoals are taking this course. 

 Indeed, for a fish whose spawning habits are so well defined both in 

 time and place, the fact that the spawning on the east coast is spread 

 over five months — May to September — of the year, would suggest another 

 conclusion — viz., that the shoals, though of the same race or group (V.), 

 may consist of several different local forms with different instincts leading 

 them to spawn at slightly different times, in slightly different regions, and 

 consequently under different conditions of environment. If we suppose 

 that these shoals, impelled by their spawning instinct at the appropriate 

 seasons, emerge from the more northern and middle portions of the North 

 Sea as well as from the neighbouring portions of the Atlantic Ocean (to 

 the west of the Shetlands), the explanation would agree with what we 

 know of the facts. It is like a succession of waves striking obliquely on 

 the shore and thus giving the appearance of the progression of the foam 

 and spray along the beach. 



This is the alternative to the extensive migration hypothesis, with the 

 distinct advantage of lending itself more readily to proof or disproof. If 

 the herring shoals fail to appear when and where they are accustomed to 

 appear, we should expect to find them at the same time in similar regions 

 not so very far away. 



This leads on to the consideration of the practical importance of these 

 studies and conclusions of Heincke. Since we believe in the rational co- 

 ordination of events which declares that the herring as individual, as race, 

 and as species is in harmony with its surroundings, then, since these races 

 have been shown to be distinct from one another, and we have signs also that 

 the surroundings are distinct, we should be able to connect any changes 

 in the movements of the herring with changes in the environment. This 

 is not a mere truism, as an example will show. The autumn and winter 

 herring-fishing off the Bohuslan coast in the Kattegat has been already 

 referred to, and the question has been much discussed — Whence come 

 these herring; from the Norwegian or Danish coast? Pettersen said 

 originally that they came in with the Danish " bank-water." This was 

 afterwards questioned,t and so a doubt arose. Heincke has, however, 

 shown that his conclusions agree with the first — viz., that these winter- or 

 sea- herring of Bohuslan are the autumn- herring of the Skagerrak and of 

 the bordering portions of the North Sea. They do not come from the 

 Norwegian spring- herring, because they form quite a different race (II.-V.). 



Thus from the study of structure we may be able to test the conclusions 

 reached with regard to the natural history of the herring by those starting 

 from the other side — viz., from the study of the surroundings. Both 

 lines of research are far from complete, but they have been well begun. 



1 J.M.B.A., 1895-97, op. cit 



