ZOOLOGY. 
317 
Dr. Cooper furnishes the following memoranda : 
"In consequence of not having sufficient alcohol for the purpose, I never preserved speci- 
mens of the various species of salmon which frequent the Columbia and the rivers of Shoalwater 
bay. excepting the heads of several species collected during the journey east of the Cascade 
range, and which were destroyed from weakness of the alcohol. Yet a few remarks upon their 
habits, made during my residence there, may not be uninteresting. 
"Salmon enter the Columbia river in large numbers about the 1st of May, and are caught 
then at Chinook Point, a few miles above Cape Disappointment. Prom this fact they are 
generally known as the " Chinook salmon," and are celebrated not only in the Territory but 
in California as the best salmon caught on the coast. The reason for its superiority when 
caught at Chinook Point is probably that, this being the first point where they can be taken 
after entering the river, they are still in fine condition, while after ascending the river they 
become thin and lose their finest flavor. It seems to be generally believed that they do not 
feed in fresh water, the stomachs of those caught further up being always empty. It may 
easily be imagined that this must soon exhaust them, and it seems almost incredible that they 
should ever be able to go up four hundred miles, over innumerable rapids and falls and against 
a current which must require their constant exertions to contend with. But by reference to 
my journal it may be seen that we found them in great numbers in the Okanagan river, at the 
49th degree, where they had every appearance of having travelled all the way from the ocean. 
Their fins and tails were so worn down as to be almost useless, their color had changed to a 
dappled mixture of red and white, and they were emaciated so as to be a mere mass of skin 
and bones. But still they struggled on up, obedient to the blind instinct which led them to 
seek the very headwaters of the river to find a fit nursery for a progeny which they should 
never know. 
"It of course excited much speculation in our minds as to the law of nature which should 
doom so many thousands of fish to certain death, and apparently, contrary to all analogy in the 
class of fishes, to die after making but one deposit of eggs. No solution of the matter was 
then suggested, but in thinking it over since, I have arrived at a theory on the subject which I 
will now state: 
"It will be observed that such large numbers of dead or dying salmon are found mostly at 
the headwaters of streams, and that they increase in number the further Ave ascend from the 
sea. It is also the fact that great numbers go up the small streams emptying into the sea from 
the Coast range, and do not there die in any quantity unless they have to ascend many falls 
and rapids. I never saw anything like the number of salmon in that condition at Shoalwater 
bay, although I have seen tons of them there. 
"Another noticeable fact is that all those seen in the Okanagan river were small, not more 
than two feet long, and very uniform in size. Besides this, they seemed to be of the same 
species as we saw further down the Columbia. They certainly were not of any species of 
trout constantly inhabiting the river, of which I had already seen three. Now, the reason I 
would assign for the 'wearing out' of some salmon annually is this : Shoals, probably com- 
posed of fish of difterent ages, enter the river, the larger and smaller keeping in distinct 
bodies. Their ova are more or less mature, perhaps according to the age of the fish, and they 
continue to ascend the river until the ova become ready for deposition. This I know often 
occurs quite near the sea, as salmon may be seen making their nests in the clear water of the 
Willopah, not more than fifteen miles from its mouth. But that it is not always so is shown by 
