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TRANSACTIONS. 217 
himself had at his place introduced a sort of training school, and 
tried experiments with food which would float on the surface of 
the water, or, at all events, not sink very deep. Mr Armistead, 
speaking of shad hatching in America, quoted a Mr Worth on the 
subject, who said that the great success achieved in the propaga- 
tion of this fish demonstrated what could be done with many other 
valuable fish. The success of the shad-hatching work carried on 
by the United States Fishery Commission had been proved beyond 
the shadow of a doubt. At first the fishermen were rather inclined 
to oppose the work, but now they were willing helpers, and the 
shad fisheries, which showed a great falling-off prior to the com- 
mencement of the work, had since wonderfully improved, and 
showed an increase in the “take” each year. The evidence, too, 
which was very voluminous, was conclusive as to the successful 
operations of the Commission. There were rivers where shad had 
never before been seen, and now, as the result of the work of arti- 
ficial propagation, they were teeming with shad. Going on to 
speak of disease among fish, Mr Armistead said where fungus 
existed it was impossible to exterminate it, but it might be pre- 
vented from attacking fish by antiseptic treatment. The problem 
of fungus epidemics was a difficult one. The fungus was 
always present, but only occasionally in an epidemic form, and 
fish could live happily in affected rivers. He was much indebted 
to Mr Allan P. Swan, of Bushmills, County Antrim, for the results 
of his interesting investigations in this matter. Mr Swan said, and 
he agreed with him, that the condition of health in fishes has much 
to do with the fungus disease. The first consequences of a low 
vitality might be a slow or imperfect excretion and epidermic 
formation. Sickly fish were attacked, and many of the fish which 
died in our rivers were no doubt the legitimate food of the fungus, 
and one of its chief means of propagation during the cold winter 
weather when development was not so rapid. The purest water 
was as favourable to the growth of fungus as any other, and pollu- 
tions were unfavourable to fungus, as the chemicals in these pollu- 
tions were apt to destroy the fungus. The life history of the 
fungus had been well worked out, and they now knew probably as 
much about it as was at all necessary, and any points left un- 
ravelled could easily be worked out to the smallest detail with time 
and patience. He thought this could not, however, be said of the 
salmon, and it was the missing link in the life history of the fish 
that required all the energies of both scientists and practical men 
