THE SCALES OF THE SALMONID^E 255 



irom the trout of many of our rivers after the second 

 year's growth. 



The development of a line of scales forming a silver bar 

 on the side of trout is an indication of its health and rapid 

 growth, and is not uncommon on our chalk streams. Mr. 

 Clinker, the Manager of the Lower Chilland Trout Hatchery, 

 Hampshire, tells me that fish thus distinguished always do 

 well in the spawning season. This, too, is quite what we 

 expect, for the rather unusual growth of scales forming such 

 a bar indicates that an abundance of the best food has been 

 within reach of such trout. 



SCALE MARKINGS 



The edges of the laminae forming the scales of a salmon 

 indicate many of the most important events of its life 

 its age, its descent as a smolt to the sea, the varying 

 amounts of its summer and winter growths, the physiological 

 alterations in its appearance due to its ova-bearing condition, 

 its first spawning visit to a river, its return to the sea, its 

 recovery there, and the fact that it has made a second or 

 even third recurrent visit to fresh waters on spawning intent. 



It is also supposed that the decrepitation of a portion of 

 the scale markings proves that a natural and successful act 

 of spawning has taken place. 



It is on this latter question that I venture to express a 

 doubt. The marking on the scales indicates that, owing 

 to genital changes, the condition of the salmon has altered, 

 and that it has visited fresh water, but it does not prove 

 that it has carried out its life's purpose and spawned in a 

 successful and natural manner. This difference must be 

 regarded as most important, for the salmon which has 

 spawned successfully may well be considered as being 

 among the vast majority of fish which perish annually, whilst 

 those fish whose attempts to reach a spawning ground or 



