Salmonidae 



13 



seems that Salmon seldom live longer than ten years or spawn 

 more than three or four times ; many spawn only once. After 

 spawning the Salmon is termed a Kelt. 



Enlarged photographs of scales of Salmonidae, presented by 

 J. A. Milne, Esq., are exhibited in a frame on the wall to the 



Fig. 6. — Scale of Salmon. 



1 marks the edge of the Smolt scale ; 2 indicates the first \vinter zone formed 

 in the sea ; 3 the spawning mark ; and 4 the second winter zone formed in 

 the sea, which has been obliterated, except anteriorly. 



right. Nos. 1 to 7 are scales of Salmon, and illustrate how the 

 age and life-history of the fish can be read on the scales. One of 

 these photographs is reproduced here (fig. 6). The scales of a 

 Salmon show concentric rings ; as the fish gi-ows the scales 

 increase in size and more rings are added. In the summer, 



