HOW THE TROUT CAME TO CALIFORNIA. 285 
For all we know it is constantly receiving acces- 
sions from the small Steel-heads which do not find 
their way to the sea. It is not always easy to tell 
where Steel-head trout leaves off and Brook trout 
begins. The Rainbow Trout occurs in the coast- 
wise brooks all the way from Oregon to the Mexi- 
can line. It abounds in Rio San Luis Rey, in San 
Diego County, and I have heard of its occurrence 
across the border in Mexico. In no two streams 
does this Coast Range trout seem to be exactly the 
same, and in all it is small, speckled, and vigorous. 
In one stream of the Redwood country, Purisima 
Creek, in San Mateo County, there is a high 
waterfall where it drops into the sea. No trout 
can climb this fall, and those who are above it have 
been there for many generations. These Purisima 
Trout, befitting their name, are the brightest in 
color of all the trout of the mountains. When the 
trout which have gone down over the Purisima 
falls reappear in other streams, as they often do, 
we can still know them by the brightness of their 
colors. 
Northward the Brook Trout, or Rainbow Trout, 
grows more distinct from its relatives. Its colors 
in Oregon and Washington are more marked, its 
scales larger, its mouth smaller. About the mouth 
of the Columbia it becomes the form known as 
Salmo irideus masont. Here no one could fail to 
distinguish it from the Steel-head. The Steel-head, 
Cut-throat, and Rainbow are all found here, -— 
three different generations of trout, each with a 
long history. Here each one is a distinct ‘‘ spe- 
cies,” beyond all doubt or question.- It is equally 
