94 THE LIFE OF THE SALMON 
When a female fish spawns she rapidly loses 23 
per cent. of her weight and a corresponding diminu- 
tion of body girth. As a kelt the descent to the 
sea is then made, and thereafter, with a sudden 
accession of feeding, a marked growth begins, so 
that the fish may soon be double its kelt weight. 
If this greatly increased bulk is to be provided 
with a scale covering, it is clear that one of 
two things must happen: either new scales must 
grow amongst the old ones, or the already existing 
scales must become enlarged—must, in fact, have 
the power of growth which the body of the fish 
possesses. 
It has been supposed by some that a shedding of 
scales takes place at certain periods of the fish’s life, 
and that new scales are formed. It has even been 
thought by some that the male salmon at the breed- 
ing season has not a covering of scales. It is true 
that at this time the male fish is remarkably smooth 
and slippery, and that the surface is not imbricated 
in any way by scale edges. This is not, however, 
from any loss of scales, but because the whole con- 
dition of the skin has altered and become thickened 
and toughened. The scales are now deeply em- 
bedded in their skin pockets, and cannot be got 
hold of properly unless the thick skin covering is 
lifted or punctured. But at no time of the fish’s 
life are young growing scales found amongst the 
existing scales, except in places where repair after 
injury is going on. There is no arrangement of 
growing rows of scales ready to take the place of 
the older scales, as teeth do in the jaws of a Green- 
