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Experiments on the Development and Growth of the Fry of the 

 Salmon from the exclusion of the Ovum to the Age of Seven 

 Months. By Mr John Shaw, Drumlanrig, Dumfriesshire. 

 Communicated by the Author.* 



There are few subjects which have hitherto afforded more 

 scope for speculative treatment than the natural history of the 

 salmon. From its birth to its mature age its history is involved 

 in a degree of obscurity which can only be removed by an ac- 

 curate and long-continued series of experiments. The medium 

 in which observations must necessarily be made, the migratory 

 habits of the fish, and the proneness of scientific men to rear 

 systems upon partial and insufficient data, rather than to ac- 

 knowledge the want of that correct information upon which 

 alone systems can securely rest, all tend to embarrass the ques- 

 tion, and discourage the investigator. These are difficulties 

 which alike beset the path of the learned and unlearned ; but 

 there is another difficulty which more particularly presses upon 

 the latter, and that is, the scepticism with which his observa- 

 tions are generally regarded by scientific inquirers. This 

 scepticism must obviously be met by increased industry and 

 caution, and by an accumulation of evidence so conclusive as to 

 overbalance the disadvantage of a defective scientific education. 

 In the observations and experiments which form the subject of 

 this paper, I have therefoi'e endeavoured to proceed with that 

 circumspection and exactness, necessary alike to convince the in- 

 credulous and to protect myself from the charge of crude ob- 

 servation. 



It was objected to the former paper which I contributed to 

 this Journal, that my observations being made upon ova taken 

 from the bed of the Nith, there was not sufficient evidence that 

 these were the ova of the salmon at all, the same streams being 

 accessible to other fish. However well satisfied I myself might 

 be of the accuracy of my observations, I felt that it was de- 

 sirable to supply this link in the chain of evidence, and I have 

 accordingly repeated my experiments from the moment when 

 the ova are excluded, preserving the skins of the parent fish 



" Read before the lloyal Society of Edinbingh on UJlli December 11137. 



