CONCLUDING REMARKS 207 



the migratory habit as a test of the trout's nature, because it may be 

 broadly said that ail trout are migratory in a greater or less degree. 

 The suggested classification is, however, worthy of support on other 

 grounds, but these involve the recognition of two distinct and separate 

 kinds of sea-trout. 



Mr. Regan, as we have seen, admits in his classification only one 

 species of trout, Salmo trutta, to which fish he ascribed a marine origin. 

 In other words he presumes that the trout is a sea-trout. 



I may interject here two definite statements of fact: — 



(i) Common Ancestor. The common ancestor of the salmon and 

 trout has not yet been discovered. 



(2) Original Habitat. It is not yet proved whether salmon and 

 trout, or one or other, have a marine or a fresh-water origin. 



Mr. Regan, however, in company with other recognised authorities, 

 finds that two " races " of sea-trout are distinguishable, though with 

 difficulty. In much the same way Mr. Calderwood distinguishes two 

 " varieties " of sea-trout. I have already given, I hope impartially, the 

 views of those who are most competent to speak on this subject which 

 of course involves the identity^ and therefore the proper classification, 

 of the " bull trout." The reader may take it that the problem of the 

 bull trout is not yet definitely solved. Such definite light as I have 

 been able to throw upon the subject is of the faintest, but I think that 

 some grounds have been given for the belief that further systematic 

 scale examination will help to guide us to more definite conclusions. 

 The scales which I have examined (they could hardly be fewer in 

 number) suggest a rate of growth in a sea-trout typical of certain rivers 

 which is far more akin to the characteristic growth of the salmon than 

 it is to the growth of that other type of sea-trout which is perhaps most 

 familiarly recognised in our rivers. Taking this fact — if it be a fact — 

 along with other characteristic differences noted by various authorities, 

 the " bull trout " would seem to me to be so distinct from that other 



