Page:Popular Science Monthly Volume 16.djvu/599

 time, the domestic animals, the dog, sheep, horse, and various breeds of cattle appear, and are subject to man; and along with them there was the cultivation of the arts of agriculture. In conclusion, he claimed that hopes of fixing the exact antiquity of man would be vain, as there were intervals of the length of which we have no record; but he was certainly an inhabitant of the earth during the Glacial period.

Does Sargassum vegetate in the Open Sea?—In reply to the questions of a correspondent in "Nature," regarding sargassum, Mr. J. J. Wild gives the following information: While on board the Challenger, during her cruise in the North Atlantic in the year 1873, he had frequent opportunity for observing this alga, and more than once saw large patches of it extending from the vicinity of the vessel to a great distance. As regards the appearance of these sargassum patches, he quotes Sir C. Wyville Thomson, who says: "They consist of a single layer of feathery branches of the weed (Sargassum bacciferum), not matted, but floating nearly free of one another, only sufficiently entangled for the mass to keep together. Each tuft has a central brown, thread-like, branching stem, studded with round air-vesicles on short stalks, most of those near the center dead and coated with a beautiful netted white polyzoön. After a time vesicles so incrusted break off, and, when there is much gulf-weed, the sea is studded with these little separate white balls. A short way from the center toward the ends of the branches, the serrated, willow-like leaves of the plant begin, at first brown and rigid, but becoming further on. in the branch paler, more delicate, and more active in their vitality. The young fresh leaves and air-vesicles are usually ornamented with the stalked vases of a campanularia. The general color of the mass of weed is thus olive in all its shades, but the golden olive of the young and growing branches greatly predominates." Mr. Wild still further quotes from the same author to the effect that sargassum is the "one notable exception" to the rule that the higher algæ do not live on the surface of the sea. Mr. H. N. Moseley, in "Notes by a Naturalist," refers to the pelagic habits of sargassum and other sea-weeds when he says, "They grow attached to rocks, as well as free, but they all produce spores only when attached."

The Salmon Industries of Oregon.—It is well known that the salmon, which is esteemed a luxury, and at certain seasons of the year is found only on the tables of the rich, is a prolific fish. A female will yield about a thousand eggs for every pound of her weight, but, of the millions of eggs deposited in spawning-beds, only a few develop to adult salmon. Numberless ova escape fertilization, floods carry them from their places of deposit, and enemies destroy both eggs and fish. Enthusiasts in fishery economy assert that in the near future salmon will be as cheap as other fish. At present, however, it is very dear, and, notwithstanding that artificial spawning is resorted to, the fish does not increase in proportion to the increasing demand. This keeps up the price, and has given rise to an important industry in the preparation of canned salmon. We glean the following concerning this industry from "Chambers's Journal": A surprising trade in this commodity has developed in Oregon, and large quantities of canned fish are exported from this source to Great Britain and Europe. Scotland and Ireland yield excellent salmon, but the canned fish may be obtained even in remote towns of the United Kingdom for half the price of the fresh. There are flourishing canneries on the Umpqua, Eraser, Royal, and Columbia Rivers. In some of these a capital of fifty thousand dollars has been invested, and twice that outlay will be required for some newly projected establishments. The fish taken from the Columbia River are nearly all 'canned,' and as many as twelve million pounds of salmon have been taken from this source in a single season. The Columbia is a river of vast extent, with an enormous body of water. Salmon run up to a distance of four hundred miles from the sea, and thus obtain ample living and spawning room in shallow places of the main stream and its tributaries. The fish selected for canning is locally known as the 'chinook salmon.' Its average size is twenty-two pounds. When taken only for local consumption, clubs and