392 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 
male dog salmon is red and his jaws are much distorted. This is also | 
true of the humpback salmon, which is small, weighing up to 6 pounds 
and having 15 anal rays. 
Among the offshoots of the Salmonide is the steelhead, which, from 
good authority, is the salmon trout, the same species as the rainbow 
trout in the streams. In point of fact the steelhead and rainbow trout 
were originally one and the same fish, so far as at present known from 
their construction, the difference in size being due to their habits and 
the extensive surroundings of the steelhead. In construction, except 
its size, the steelhead is a trout, but in habits a salmon. ‘The rainbow — 
trout may become a salmon trout (or steelhead) when its habits are 
anadromous, which could occur through accident, such as an unusual 
freshet in which the rainbow trout is washed into the estuaries of the | 
rivers and the sea. The rich food and boundless extent of territory off 
the mouths of rivers account for his increase in size and strength. This 
growth is noticed in the salmon as being comparatively insignificant 
while remaining in fresh water, but rapid upon its first visit to the sea. 
Fish food is most plentiful in the ocean near the estuaries of the rivers, 
as the influence of the fresh-water stream is felt many miles at sea, 
causing an abundant growth of marine vegetation or vast pastures, 
attracting the smaller fish and crustacea upon which the salmon feed, 
returning yearly to their native rivers to spawn. 
Very respectfully, J. J. BRICE, 
Commander, U. S. Navy- 
Hon. MARSHALL MCDONALD, 
United States Fish Commissioner. 
Lary’ 
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