47 0 Proceedings of Royal Society of Edinburgh. [sess. 
(2) There is no example of the establishment or maintenance of 
a commercial salmon fishery upon any river in North America 
which has depended for its yield upon artificial culture, unsupported 
by restrictions upon netting, or by accessible spawning grounds. 
According as either one or other of the two latter factors has 
been neglected, the yield of the river has declined. 
There are eight or nine salmon hatching stations in Canada. 
Three of them supply the province of Nova Scotia and the river St 
John in New Brunswick. The work of these three hatcheries will 
not be included in this review, as special circumstances have 
rendered the compilation of exact statistics in respect of them more 
difficult than ordinary. Their inclusion would make no difference 
to the results discovered in this paper. With these exceptions 
salmon culture by the State in Canada has been confined to the 
five rivers or districts which will now be discussed. Private efforts 
seem to have been few and far between, and are of little account. 
The Canadian Government has always supplemented its fish 
cultural work by a vigorous administrative policy. A system of 
licenses has long been established. Netting stations have been 
reduced wherever advisable and possible, nets are confined to tidal 
waters, and the upper waters protected and rendered accessible to 
salmon. The proper way in which to judge of the columns of 
figures representing the yield of the river and the plantation of fry 
in the following tables may be open to question. In the writer’s 
opinion the comparison of one year with another is very misleading. 
Our knowledge of fish life is far too fragmentary to allow of a pro- 
ceeding which assumes so much. Lt seems better to compare the 
averages of succeeding periods of four years’ duration each; and 
the following tables, dealing with the Fraser, the Ristigouche, the 
Miramichi and the Saguenay rivers and districts, have been pre- 
pared with this object in view. 
It should be noted that in order to decide how far the output of 
fry has affected the yield, the average output of fry for any four- 
year period in the tables can be compared with the average yield 
for the immediately succeeding four-year period ; that is to say, the 
average for the period ending 1882 should be contrasted with the 
average yield for the period ending 1886, and so on to the end of 
the table. 
