Salmonidz 303 
strongly and often extravagantly hooked, so that either they 
shut by the side of each other like shears, or else the mouth 
cannot be closed. (2) The front teeth become very long and 
canine-like, their growth proceeding very rapidly, until they 
are often half an inch long. (3) The teeth on the vomer and 
tongue often disappear. (4) The body grows more compressed 
and deeper at the shoulders, so that a very distinct hump is 
formed; this is more developed in the humpback salmon, but 
is found in all. (5) The scales disappear, especially on the 
back, by the growth of spongy skin. (6) The color changes 
from silvery to various shades of black and red, or blotchy, 
according to the species. The blue-back turns rosy-red, the 
head bright olive; the dog-salmon a dull red with blackish bars, 
and the quinnat generally blackish. The distorted males are 
Fie. 229.—Quinnat Salmon, Oncorhynchus tschawytscha (Walbaum). 
Monterey Bay. (Photograph by C. Rutter.) 
commonly considered worthless, rejected by the canners and 
salmon-salters, but preserved by the Indians. These changes 
are due solely to influences connected with the growth of the 
reproductive organs. They are not in any way due to the 
action of fresh water. They take place at about the same time 
in the adult males of all species, whether in the ocean or in the 
rivers. At the time of the spring runs all are symmetrical. 
In the fall all males, of whatever species, are more or less dis- 
torted. Among the dog-salmon, which run only in the fall, 
the males are hook-jawed and red-blotched when they first 
enter the Strait of Fuca from the outside. The humpback, 
taken in salt water about Seattle, have the same peculiarities. 
The male is slab-sided, hook-billed, and distorted, and is re- 
