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simply due to facing the flood tide. Afterwards they enter the deepest parts of the stream and swim straight up, with few interruptions. Their rate of travel on the Sacramento is estimated by Stone at about two miles per day ; on the Columbia at about three miles per day.
As already stated, the economic value of any species depends in great part on its being a "spring salmon.” It is not generally possible to capture salmon of any species in large numbers until they have entered the rivers, and the spring salmon enter the rivers long before the growth of the organs of reproduction has reduced the richness of the flesh. The fall salmon cannot be taken in quantity until their flesh has deteriorated; hence the "dog salmon” is practically almost worthless, except to the Indians, and the hump-back salmon is little better. The silver salmon, with the same breeding habits as the dog salmon, is more valuable, as it is found in Puget sound for a considerable time before the fall rains cause the fall runs, and it may be taken in large numbers with seines before the season for entering the rivers. The quinnat salmon, from its great size and abundance is more valuable than all other fishes on our Pacific coast together. The blue-back, similar in flesh but much smaller and less abundant, is worth much more than the combined value of the three remaining species.
The fall salmon of all species, but especially the dog salmon, ascend streams but a short distance before spawning. They seem to be in great anxiety to find fresh water and many of them work their way up little brooks only a few inches deep, where they soon perish miserably, floundering about on the stones. Every stream, of whatever kind, has more or less of these fall salmon.
It is the prevailing impression that the salmon have some special instinct which leads them to return to spawn in the same spawning grounds where they were originally hatched. We fail to find any evidence of this in the case of the Pacific coast salmon, and we do not believe it to be true. It seems more probable that the young salmon, hatched in any river, mostly remain in the ocean within a radius of twenty, thirty or forty miles of its mouth. These, in their movements about in the ocean, may come into contact with the cold waters of their parent rivers, or perhaps of any other river, at a considerable distance from the shore. In the case of the quinnat and the blue-back, their “instinct " leads them to ascend these fresh waters, and in a majority of cases these waters will be those in which the fishes in question were originally spawned. Later in the season the growth of the reproductive organs leads them to approach the shore and to search for fresh waters, and still the chances are that they may find the original stream. But undoubtedly many fall salmon ascend, or try to ascend, streams in which no salmon was ever hatched.
It is said of the Russian river and other California rivers, that their mouths in the time of low water in summer, generally become entirely closed by sand bars, and that the salmon in their eagerness to ascend them, frequently fling themselves entirely out of water on the beach. But this does not prove that the salmon are guided by a marvelous geographical instinct which leads them to their parent river. The waters of Russian river soak through these sand bars and the salmon “instinct,” we think, leads them merely to search for fresh waters.
This matter is much in need of further investigation; at present, however, we find no reason to believe that the salmon enter the Rogue river simply because they were spawned there, or that a salmon hatched in the Clackamas river is any
the more likely on that account to return to the Clackamas than to go up the Cowlitz or the Deschûtes.
“At the hatchery on Rogue river, the fish are stripped, marked and set free, and every year since the hatchery has been in operation some of the marked fish have been re-caught. The young fry are also marked, but none of them have been re-caught.” This year
the run of silver salmon in Frazer's river was very light, while on Puget sound the run was said by the Indians to be greater than ever known before. Both these cases may be due to the same cause, the dry summer, low water and consequent failure of the salmon to find the rivers. The run in the sound is much more irregular than in the large rivers. One year they will abound in one bay and its tributary stream and hardly be seen in another, while the next year the condition will be reversed. At Cape Flattery the run of silver salmon for the present year was very small, which fact was generally attributed by the Indians to the birth of twins at Neah bay.
In regard to the diminution of the number of salmon on the coast. In Puget's sound, Frazer's river and the smaller streams, there appears to be little or no evidence of this. In the Columbia, river the evidence appears somewhat conflicting; the catch during the present year (1880) has been considerably greater than ever before (nearly 540,000 cases of 48 lbs. each having been packed), although the fishing for three or four years has been very extensive. On the other hand, the high water of the present spring has undoubtedly caused many fish to become spring salmon which would otherwise have run in the fall. Moreover, it is urged that a few years ago when the number caught was about half as great as now, the amount of netting used was perhaps one-eighth as much. With a comparatively small outfit the canners caught half the fish, now with nets much larger and more numerous, they catch them all, scarcely any escaping during the fishing season (April i to August 1). Whether an actual reduction in the number of fish running can be proven or not, there can be no question that the present rate of destruction of the salmon will deplete the river before many years. A considerable number of quinnat salmon run in August and September, and some stragglers even later; these now are all which keep up the supply of fish in the river. The non-molestation of this fall run, therefore, does something to atone for the almost total destruction of the spring run.
This, however, is insufficient. A well ordered salmon hatchery is the only means by which the destruction of the salmon in the river can be prevented. This hatchery should be under the control of Oregon and Washington, and should be supported by a tax levied on the canned fish. It should be placed on a stream where the quinnat salmon actually come to spawn.
It has been questioned whether the present hatchery on the Clackamas river actually receives the quinnat salmon in any numbers. It is asserted, in fact, that the eggs of the silver salmon and dog salmon, with scattering quinnat, are hatched there. We have no exact information as to the truth of these reports, but the matter should be taken into serious consideration.
On the Sacramento there is no doubt of the reduction of the number of salmon; this is doubtless mainly attributable to overfishing, but in part it may be due to the destruction of spawning beds by mining operations and other causes.
As to the superiority of the Columbia river salmon; there is no doubt that the quinnat salmon average larger and fatter in the Columbia than in the Sacramento and in Puget sound. The dif
ference in the canned fish is, however, probably hardly appreciable. The canned salmon from the Columbia, however, bring a better price in the market than those from elsewhere. The canners there generally have had a high regard for the reputation of the river, and have avoided canning fall fish or species other than the quinnat. In the Frazer's river the blue-back is largely canned, and its flesh being a little more watery and perhaps paler, is graded below the quinnat. On Puget sound, various species are canned; in fact, everything with red flesh. The best canners on the Sacramento apparently take equal care with their product with those of the Columbia, but they depend largely on the some. what inferior fall run. There are, however, sometimes salmon canned in San Francisco, which have been in the city markets, and for some reason remaining unsold, have been sent to the canners; such salmon are unfit for food, and canning them should be prohibited.
The fact that the hump-back salmon runs only on alternate years in Puget sound (1875, 1877, 1879, etc.) is well attested and at present unexplained. Stray individuals only are taken in other years. This species has a distinct “run," in the United States, only in Puget sound, although individuals (called “lost salmon") are occasionally taken in the Columbia and in the Sacramento.
THE key to the zoological affinities of Agalma, the adult struc
THE SIPHONOPHORES. 11.—THE ANATOMY AND DEVELOPMENT OF AGALMA (CONTINUED).
BY J. WALTER FEWKES. 'HE
ture of which has been given in a previous article, is to be found in its embryology or the development from the egg. To that subject I propose to devote the present article, as it is impossible in the case of this jelly fish, to discuss its morphological relationship from the study of anatomy alone.
In this discussion I shall consider, in the first place, the development of the Agalma from the egg, and in the second, the growth of new buds along the axis to form those new parts, the adult forms of which have already been described in some detail. The former division includes the consideration of the changes in form which the colony as a whole passes through in the growth from an egg to an adult like Fig. 1; the latter, the development of each of the different members of the community, or their growth from buds formed on an axis already well developed.
1 NATURALIST, 1880, p. 617.
I. DEVELOPMENT OF THE EGG. The new Agalma always begins its growth from an egg.
I know of no case where any other method of origin than from an egg takes place among Siphonophores. Alexander Agassiz describes in Agalmopsis cara a reproduction by a bud from the stem, and says that this bud has a well-developed float before it separates from the stem or axis. In Agalmopsis picta, a species closely allied to Agalmopsis cara, no such budding of a new colony takes place. In the excellent volume already quoted, entitled “Seaside Studies in Natural History," it is suggested that those organs which I have called “tasters," drop off and develop into new colonies. I consider this supposition improbable as far as any known genus of tubular jelly fishes is concerned. In the genus Agalma, as before stated, reproduction is always from the egg.
I was fortunate enough to find in the glass vessel in which the first Agalma captured by me was confined, that the water was filled with minute transparent spheres, no larger than the head of a pin. They floated about in the liquid, and were not limited to any definite depth, but when the contents of the glass became quiet, all rose to the surface, and thickly crowded together, covered it like so many small oil-globules. When they had collected in this way, I was able by means of a watch crystal to skim them off, and transfer all into a more convenient receptacle for study.
These little oil-globule-like spheres were originally cast into the water from the female sexual bells, and are eggs, from each one of which grows a new Agalma. The female bells are found in grapelike cluster just below the feeding polyps, and appear to take the form of individuals, which have apportioned to themselves the single function of reproduction of new Agalmata. They have no stomach nor mouths, but draw their nourishment from the cavity of the axis into which it has been poured by those individuals of the colony, which do all the eating for the Agalma. Each bell contains a single egg, and after that egg has been cast, the bell withers up, or is absorbed into the stem, or sometimes before the egg escapes, breaks loose from its connection with the axis, and drops into the water with the contained egg. The last process takes place by a rupture of the pedicle by which the female bell is hung upon the axis of the Agalma.
? The authors state that they have never seen these “closed Hydræ" drop off, but they suggest that it “ seems natural to suppose that they do separate from the parent stock” to found new communities.-Sea-Side Studies, p. 80.