58 OBSERVATIONS ON ACCLIMATISATION OF THE TEUE SALMON. 



fisli, had they been permitted to migrate to the sea this last 

 and the preceding spring, should by this time on returning 

 have developed into mature salmon weighing as many or 

 more pounds as they now do ounces. Should the few remain- 

 ing salmon and their progeny, if reared, be maintained under 

 their existing artificial conditions there is, I fear, but little 

 prospect of their subserving any other purpose than that of 

 confirming the results of previous experiments, and thereby 

 demonstrating that the species will not develop to its normal 

 size and quality if constantly restrained from spending, as is 

 its nature, a large portion of its existence in saltwater. 

 With the view of assisting as far as possible towards the 

 successful conduct of the experiments that may be continued, 

 and towards lessening to the greatest extent the delterious 

 action upon the fish cultivated of the parasitic fungus which 

 represents their most formidable enemy. I would submit 

 the following suggestions : — 



In the first place, it is desirable that more than ordinary 

 care should be exercised in the manipulation of these valuable 

 fish for artificial propagation. During the Conferences at 

 the International Fisheries Exhibition, London, 1883, at 

 which I had the privilege of being present, one of the most 

 important papers contributed was that by Professor Huxley 

 on " Fish Diseases." In this paper the fatal malady caused 

 by or associated with the fungus, Saprolegnia ferax, was 

 specially doalt with, and in the discussion that followed many 

 new and valuable data were elicited. In this direction Mr. 

 Wilmot, the Chief Commissioner of the Canadian Fisheries, 

 bore testimony to the fact that at the hatching stations in 

 Canada they formerly lost a very large number of the salmon 

 manipulated through the fungus. " Eound the tail, where 

 the men had caught the fish, this fungoid growth appeared 

 and spread until the fish was killed." Also, in handling the 

 salmon " three or four finger marks might be left across the 

 fishes back ; a few days after they invariably found three or four 

 stripes of fungoid growth, and the fish invariably died." In 

 order to combat the mortality from this cause, india-rubber 

 gloves were supplied to the hatcheries for the manipulation of 

 the fish and have been used ever since with gratifying results, 

 it being found that the salmon were much less liable to 

 injury and to the attacks of the fungus when so treated. 

 Similar simple mechanical appliances might undoubtedly be 

 profitably introduced at the hatchery on the River Plenty 

 for the future handling of the survivng fish. 



While the prevention of the disease should undoubtedly be 

 advocated as being of primary importance, the means that 

 may be adopted for its cure comes next in order for consider- 

 ation. At various aquaria the rubbing of the fish affected 



