484 Proceedings of Royal Society of Edinburgh. [sess. 
planted each year. Each year, too, some of the adults have been 
left in the stream and lakes to breed naturally. Notwithstanding 
all these precautions, the experimenter declared in 1900 that there 
had been no increase in the yield, and that he was still awaiting 
the return of his artificially propagated fry. It is not clear how 
the yield of this river has been arrived at, nor what observations 
have been made regarding the number of fish congregated below 
the dam each year. Presuming these objections to have been dis- 
counted, the experiment throws instructive light upon many 
theories, including the contention that a normal yield can be in- 
creased abnormally within a given period by artificial cultivation. 
The, table printed below shows the yield of white fish in the 
Great Lakes for certain years. It is calculated (U.S.F.C. Bui., 
vol. xiii. pp. 211, 217) that not less than 2,020,000,000 white 
fish fry were planted, principally in the Great Lakes, prior to 1894 
by the three distributing agencies, the Canadian Government, the 
U.S. Fish Commission, and the Commissioners of the American 
States bordering on the Lakes. There appears to have been no 
decrease in the numbers planted more recently, as in 1901 the 
plants of the U.S. Fish Commission alone amounted to upwards of 
300,000,000 fry. 
Total White-Fish Catch in the Great Lakes. 
1880. 
1890. 
1897. 
lbs. 25,200,000 
19.900,000 
9,600,000 
1899. 
8,096,366 
The above example brings forcibly forward the particular in 
which some departments of the fishery administration of the 
United States seem to have failed. The efforts of the Federal Fish 
Commission to increase the production of its waters are confined to 
fish culture, as the control of legislation and administration is 
entirely in the hands of the State authorities. Hence the necessary 
protective measures are not always taken ; and for this reason, if 
for no other, the work of the United States Commission appears to 
have been fruitless, or nearly so, in many cases. A like disappoint- 
ment probably awaits those in this country who look to the restora- 
tion of our rivers by means of salmon culture, should open and un- 
polluted streams and netting restrictions be not at the same time 
insisted upon. 
