THE SALMON FAMILY 63 
T have chosen two photographs of scales removed 
from the shoulder of a fourteen-pound cock fish, caught 
in the Tay on May 8th, 1911. 
First, let us examine the illustration of the complete 
scale. 
The smooth portion is that part of the scale which is 
visible on the body of the fish. The portion showing 
rings is that part of it which is buried in the skin and 
overlapped by adjacent scales. The broken edges, and 
the apparent absence of rings of growth on the smooth 
part of the scale, are due to the friction to which this 
portion of the scale is exposed. The centre of growth 
is seen as a complete little circle ; this was the original 
scale on the larval fish. Round this centre are several 
complete rings indicating the growth of the parr during 
its first year. Outside these rings we have further rings 
due to the growth of the parr during its second year in 
fresh water. The lower portion of the second year rings 
have come on to the exposed portion of the scale, and 
so have been rubbed down. The rings of growth, so 
far, are very narrow, as the growth of the parr in fresh 
water is very slow, but just outside the completion of 
the narrow rings are seen two broader rings (though these 
two rings are not nearly so broad as subsequent ones). 
The two broader rings are due to the increased growth 
of the smolt in tidal water; then follow twenty-two very 
much broader rings, which indicate the growth during 
the fish’s first summer in the sea; next, six narrow rings 
for the first winter’s growth in the sea; again, twenty- 
