RESULTS OF SALMON MARKING 61 



and the growth of the fish with its many surprises, 

 must be viewed in strict relation to this divided or 

 dual habit of marine sojourn. It would be out of 

 place to compare at a given time a fish which had 

 returned to fresh water after a short sojourn in the 

 sea with a fish which had been feeding and growing 

 for twelve or eighteen months. When a classification 

 according to short and long periods is adopted, there 

 is still much that is difficult to understand and great 

 variation in results, but the life of the salmon seems 

 to be cleared of that obscurity which has for so long 

 defied the penetration of many and varied search- 

 lights. Moreover, it is also necessary to give atten- 

 tion to the localities from which fish come, since what 

 is considered a large fish in one place may be a com- 

 paratively small one in another, so that fish of similar 

 weight are not necessarily of similar class or age. 

 Further, it seems necessary to have regard to the 

 particular years in which records are acquired, and to 

 compare different periods, when treating the subject 

 broadly. Classification by weight, length, or other 

 particular is only useful in questions of migration 

 when fish of one locality are being dealt with. I was 

 never so much impressed with the necessity for com- 

 paring only similar periods till a combined analysis 

 of Scottish and Irish results was attempted. It has 

 been my intention in writing these chapters to avoid 

 tables of statistics, because of their rather formidable 

 and uninteresting appearance, but in the present 

 instance I must ask the indulgence of the reader in 

 giving the data in as condensed a form as possible 

 from which deductions are made. 



