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mind to deduce any other conclusion than this, that the in- 

 ternal parasites were sometimes associated with the external 

 in the production of disease and death. On the other hand 

 there were some instances where no external parasites 

 were found, but there were hundreds of thousands of small 

 parasites of the entozoa character, which brought about 

 the same fatal issue. In illustration he might mention that 

 a few years ago one particular kind of parasite, which he 

 he had shown to the Prince of Wales and Prince Napoleon 

 the night before, killed hundreds and thousands, and, as 

 one French author said, hundreds of thousands, of coarse 

 fish. Professor Huxley had shown in a most interesting 

 manner that the germs of Saprolegnia might be propagated 

 by other bearers than the salmon itself ; and here again he 

 would point out that there was a parallelism with the 

 internal parasites, they being conveyed by bearers or inter- 

 mediate hosts. The adult parasite required a change of 

 hosts, passing from small insects to the fish. That was the 

 case with one which was very common in the perch, and 

 other coarse fish, and the higher parasites or the larger ones, 

 the cestodes, were also propagated through the means of 

 intermediary bearers. It might interest the audience if he 

 were to state a curious fact in connection with parasites in 

 fish as he might not have another opportunity of doing so, 

 owing to his numerous engagements. Whilst showing a 

 specimen of a large ligula, so common in fresh-water fish, to 

 Prince Napoleon, he reminded him that they were what 

 were called in Italy " Maccaroni piato," and were constantly 

 eaten there as a delicacy, being supposed to be fleshy 

 growths inside of fish. Fortunately it might be hoped that 

 this particular parasite would be destroyed with even the 

 very slight cooking, and even if not cooked, there was no 

 reason to suppose that the ligula would be transformed 



