Manchester Memoirs, Vol. Ivii. (191 3), No. ;$. 15 



highest " redds " but spawn much nearer to the sea. 

 According to this the summer fish has not such a long 

 lime of fasting, neither has it so far to travel during the 

 fast. Remembering all these circumstances, it is not 

 astonishing to find that so few spring fish survive to spawn 

 a second time. 



It is true that the spring fish, at the time they enter 

 the river, are in much better condition than the summer 

 fish, but the study of scales clearly shows that the sojourn 

 in the river is more fata! to the former than it is to the 

 latter. 



A practical result that follows from this consideration 

 is that excessive fishing in the summer is slightly more 

 harmful than excessive fishing in the spring, because the 

 chances that the fish caught would have returned a second 

 time to spawn are greater in the case of the summer fish 

 than they are in the case of the spring fish. 



As bearing to some extent on the question of the 

 racial differences in salmon, it is interesting to turn now 

 to the consideration of the time of year when the fish 

 return to the river to spawn for the second time. If there 

 are two distinct races of salmon, the spring race and the 

 summer race, it might he expected that the instinct to 

 return to the river would be felt at the same time of year 

 in successive spawning efforts. We should expect the 

 spring fish to come up to spawn in the spring and the 

 summer fish in the summer. I?ut there seems to be no 

 such law governing the return of the fish to the river (see 

 Table 9). 



There were in the series examined twenty-two spring 

 fish, and of these nineteen returned to the river to spawn 

 for the second time in the spring, and there were fifty-one 

 summer fish, and of these only fifteen returned for the 

 second time in the summer. It is evident, therefore, that 

 in a considerable number of cases the spring fish may 



