48 THE SALMON. 



anglers, and propounded so far back as 1686 (De His- 

 tona Piscium, by Rae and Willoughby), that the male 

 of the young salmon comes to sexual maturity in its parr 

 state. The hypothesis, however, was crushed by its ap- 

 pearing on investigation that the fish remaining during 

 the second year consisted of both males and females, the 

 milts of the males being fully developed, while the roe 

 of the females was discernible only by a microscope. 

 Thus in the end (for it seems the end), the disputants 

 on this point have been left all in the wrong, or all in 

 the right, and consequently a large proportion of them 

 on both sides not only disappointed, but unconvinced. 



To account for the double or mixed response of the 

 Stormontfield oracle to the question between the one- 

 year and the two-year theories, doubts have been raised 

 by the partisans of both views, whether the circumstances 

 under which the fish were reared in and let out of the 

 pond, were not such as to render the results unreliable 

 as indications of what would have taken place had the 

 fish been in their natural position and freedom, one side, 

 of course, maintaining that these circumstances acceler- 

 ated, and the other that they retarded, the natural growth 

 and movements. It was said of Mr. Shaw's experiments 

 that the two-years' fresh- water residence of the fry was 

 ascribable to the " difference of temperature between the 

 waters of the Nith, from which the ova were taken, and 

 the waters of the ponds in which they were hatched and 

 reared." But where is the evidence as to what was the 

 difference in temperature, or whether there was any at 

 all ? On inspecting Mr. Shaw's Observations for in- 

 formation on this point, we can only find that the tern- 



