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 INIr 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 lieen 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 he 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 



