RESULTS OF SALMON MARKING 69 
have adopted the short period or those which have 
adopted the long period. The average kelt in Scot- 
land is, however, about 21b. heavier than the average 
kelt of the Irish records, the weights beingrespectively 
77% lb. and practically 54 1b. If individual districts 
in Scotland were compared, it could be shown that 
the same variation exists between kelts of say the 
Helmsdale and the Tay, the former being, so far as 
these records show, 63 Ib. and the latter 9 lb.; but 
the purpose of the above tables being to elucidate 
the divided migration, the fact that such differences 
exist in the one country only serves to bring out 
more forcibly the fact that this divided migration 
is independent of the weight of the fish. The sub- 
ject of the increase of weight in kelt to clean condition 
will have to be dealt with more fully later, but to 
complete the statement as to the tables the increase 
may be briefly given here. The Scottish returns 
show an average increase in the short period of 
6 lb., in the long period of 10 Ib. ; the Tvish records, 
in the short period 4} lb., in the long period 
108 Ib. 
In the previous chapters the life of the smolt and 
grilse has been traced, and evidence has been educed 
to show that the smolts which descend in May at 
the age of fully two years make their first reappear- 
ance in fresh water at two separate seasons and in 
two stages of life, viz., in a year as grilse, and in a 
year and a half, having spent two winters in the 
sea, as small spring fish. This in the life of the 
salmon is the commencement of the divided migra- 
tion. The tables just given prove the continuance 
