Manchester Memoirs, Vol. hit. (191 3), No. 3. 17 



attempt to spawn in two consecutive years, while 55 

 returned to spawn the second time in the year but one 

 following that in which they spawned for the first time. 



Conclusions. 



Up to the present time all the investigations with 

 regard to the life-history of the salmon have been of very 

 great interest on account of the many unexpected results 

 which have been obtained. The collection of scales under 

 discussion appears to present quite a number of unlooked- 

 for irregularities. The fish, according to the scales, 

 remained in the sea for various lengths of time previous 

 to spawning. There appears to be no rule which deter- 

 mines the length of stay in the sea between the first and 

 second spawning periods. In fact, so far as the results go, 

 it would seem that there is no definite law governing the 

 migrations of the salmon ; each fish is a law unto itself, 

 living its own independent life, travelling about when it 

 pleases. From a research of this kind, the " shoal" of 

 salmon entering a river is put before us in quite a different 

 light. From these results it can be no longer considered 

 to consist of a number offish of similar ages which have 

 lived side by side all their lives. The shoal more closely 

 resembles a crowd of people entering a concert hall. In 

 each case the aim in view appears to be the only thing in 

 common ; the salmon of varying ages enter the river to 

 spawn just as the people of various kinds crowd into the 

 hall to hear the concert. 



During the past two or three years many doubts have 

 arisen with regard to the salmon, and theories have been 

 formed in the endeavour to explain the very striking 

 differences between what are known as "spring" and 

 " summer " fish. One of these theories is that the " spring " 



