THE SCALES OF THE SALMON ID^E 273 



its ova during the following spawning season, then only 

 a relative proportion of the assumed sixteen fresh annual 

 markings could possibly have occurred. But if we count 

 the number of rings at B, we shall find no less than sixteen 

 have been added, though the salmon cannot possibly have 

 been in the sea more than eight months, and therefore the 

 theory of sixteen rings is not applicable in this case. The 

 salmon cannot have spawned in January, reached the sea 

 in April, run up in time to spawn again in the winter, and 

 have spent more than eight months in the sea. Yet in- 

 adequate as this time may seem, Nature is a very rapid 

 architect, and there is no other probable deduction to be 

 drawn from this scale if its markings are to be relied on, 

 other than that the fish has discharged its ova twice in 

 twelve months, some four months of which must have been 

 spent in fresh water. 



The irregular manner in which these decrepitations eat 

 up or destroy the concentric markings will be noticed in the 

 scales shown on Plate XXX. 



The scale shown in Plate XXXI. kindly sent to me 

 by Mr. Hutton is in my opinion most instructive. Mr. 

 Hutton has marked on the photo that it is " a hen spring fish 

 of thirty-four pounds weight, caught on April 26th, 1909," 

 and that "it has spawned once." To me it appears that 

 the date of this first spawning condition, or the passing of 

 its ova, must have been at least fourteen or fifteen months 

 prior to the date of its being killed. The size and number 

 of the new concentric markings show that they cannot have 

 been added to the scales since the more recent spawning 

 season, and their growth has been strictly in proportion to 

 the increasing bulk of the fish. 



This scale also shows that the salmon's condition was 

 perfect at the time it was captured, for no decrepitation has 

 yet taken place in the outer edge of the scale which is smooth 



19 



