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duced from the waters of the Asiatic shores of the North Pacific or from the American shores of the North Atlantic? If artificially introduced, of which there can be no doubt-from which direction does the extent and character of the traffic of our commercial intercourse make it most probable that the species came or was brought ? By water on the steamships from Japan, or by railroad three thousand miles overland from the Atlantic seaboard ?
With the completion and operation of the trans-continental railroad, our oyster men, many of whom have a large capital invested in the business, commenced the importation of small oysters (0. virginica) from the Atlantic side, by the car load, for planting in San Francisco bay, where in a season or so they attain a merchantable size, growing exceedingly fat; as yet, efforts to propagate them have not been successful; but the importation still continues as before, the profit to the oyster planter being simply through increase in size and not from multiplication of numbers by propagation.
There is no similar traffic with Japan, and it is hardly possible that the fry of Mya arenaria, if it did adhere to the bottom of the steamers in Japanese parts would be able to hold on for so long a time or for so great a distance with the friction of the water against the bottom of the steamer constantly operating to sweep it off.
Native oysters are also imported from various points in Washington Territory, and planted in the bay, but we have no knowledge of the Mya existing at any point in the region from whence these latter oysters are brought.
In the presence of the fact of the rapid increase of this truly excellent edible, next to the oyster the most valuable either as human food or fish bait, of any of this class of food, and the inference from its spreading so readily in San Francisco bay, that other places along the coast might prove equally congenial to it, it would be a wise, public spirited act if the captains of our coasting vessels would take the trouble and incur the slight expense attending the planting of this clam at such points as their vessels touch at in the ordinary course of business.
Since the manuscript of the foregoing matter was sent to the NATURALIST, I have received specimens of Mya arenaria from my friend, Dr. C. L. Anderson, of Santa Cruz, for identification. Santa Cruz is on the coast at the northerly end of Monterey bay, about seventy-two miles south of the entrance to San Francisco bay. The specimens are rather under, than of, the usual size, and were obtained at the mouth of a lagoon near Santa Cruz.
In a few years we may look for its distribution southerly and along and around Monterey bay, the shores of which are well adapted for this species. As to its introduction at Santa Cruz, I hope to be able to give more particular information hereafter.
THE SQUID OF THE NEWFOUNDLAND BANKS IN ITS RELATION TO THE AMERICAN GRAND:
BANK COD FISHERIES.
BY H. L. OSBORN.
THE broad continental plateau which fringes our eastern coast
shallows known in sailor language as "banks." These banks have, on the average, a depth of thirty fathoms, though in some places but seven or eight fathoms, and are a favorite resort of the several species of our most important food fishes, visiting the places to prey upon the many forms of marine invertebrates covering these favoring spots in most luxuriant profusion. In most cases the banks are not extensive, not more than from ten to twenty miles in length, but this rule finds a notable exception in the case of the Grand Bank, off Newfoundland. This shoal is in shape nearly an equilateral triangle; its base is two hundred and seventy miles long, running east, north-east, and lying somewhat east of south-east from the island. This northern edge, furthermore, is sixty miles distant from land, and the intervening water has an average depth of eighty-five fathoms. The edge of this shoal is very clearly defined, the water along the northern limit falling suddenly, in the distance of only a mile or two, from thirty to sixty fathoms, while, on the other sides, the descent is frequently very rapid from thirty to one hundred and eighty fathoms. It has been noted as the most favorable grounds for the capture of the cod since before 1740, at which time seventy vessels from Gloucester alone, scoured the banks, and since which time the number has fluctuated, till at present more than four hundred schooners are engaged in the pursuit. The problem of bait has always been a troubling one to this enormous fleet. I am told that in early days salt bait of clams or fish was in universal use, but of late some sort of fresh bait has seemed a necessity, and the squid has become the favorite form. This they are forced to procure at Newfoundland, and they have thus opened a new traffic to the people of the island, and caused, too, at times, much hostility and ill-feeling.
During the summer and fall of 1879, I had the opportunity of spending three months on a codfishing schooner, for the purpose of making zoological collections, and also of studying the men and their methods; this gave me a chance to visit a large number of harbors, and to study in some detail the matter of bait.
The bait used during the latter part of the year is the squid; not Loligo pealii Les., the common form of the ocean waters south of Cape Cod, but Ommastrephes illecebrosa Quatr., a more northern species readily distinguished by its movable eyelids. So many good descriptions and figures of this species are in the reach of every one, that any description of the creature is unnecessary in this place. For accurate description of the wonderful changes of color in the integument, I would refer the reader to Professor Verrill's account?.
The squid does not appear early in the year, during which time the herring, Clupea harengus, and the capelin, Mallotus villosus, are used, but “strikes” late in June or early in July, touching first upon the southern points of the island. The natives and the fishermen agree in the opinion that the squid migrates steadily northward during the season, appearing first in the northern harbors two weeks later than in the southern, and finally lingering at northern points in the island after they have entirely disappeared from those further south. One is induced, moreover, to believe in a migration among the squid, from the intermittent manner in which they are captured. At one time they are taken as fast as they can be hauled in, while, again, scarcely any can be caught. Furthermore, captures of different times will often average very differently in size, indicating that those of the same ages move in the same schools, and that one school is replaced by another. Thus on one day we secured a large number of very large squid, the largest measuring 290 mm. and the average 265 mm. from base of tentacles to tip of tail, but on the following day could obtain none whose length was greater than 190 mm.
1 Invertebrates Vineyard Sound, pp. 442-443, 1874.
Evidence is not wanting to show that the squid do sometimes occur on the Grand Banks. Vessels are reported to have caught their bait while at anchor there, and yet I can but regard this as the exception, and I believe that the habit of the squid is to remain during the summer quite near shore. In examination of the stomach contents of the cod, I saw nothing to indicate the squid's presence on the banks. This to be sure is negative evidence, yet it carries some weight.
Squid jig. The sole mode of capture of the squid is called “jigging," a term derived from, and descriptive of the process. The only gear is a peculiar hook called a "jig,” and a couple of fathoms of “mackerel” line. No bait is employed. The jig is of lead, two inches or thereabouts in length, armed at its base with sharply pointed unbarbed pins radially arranged, and curving upward and outward as represented in the accompanying figure.
The jigging is conducted in water of from eight to ten feet, usually from small boats, but occasionally from the vessel's side. The jig is allowed to sink nearly to the bottom, where it is kept constantly vibrating up and down, till the squid is felt upon it. Frequently two jigs are managed, one in each hand.
In its mode of taking the hook, the squid differs from any other animal I have ever met. In place of a nibble followed by a snap with the subsequent struggle for escape, there is a sensation as of some one grasping the hook with his fingers. The squid does not use his mouth in “biting,” but merely clasps his tentacles round the jig. The pain from the sharp pins doubtless induces him to escape instantly, but the fisherman who is constantly jerking the jig up and down, pulls in as rapidly as possible, entangling the squid's arms among the pins, and drawing him through the water so fast that escape is impossible.
The instant he emerges from the water he contracts his body, discharging through his siphon a jet of salt water. This is followed by a sucking in of the air by successive respiratory acts, till in its middle portion his cylindrical body has become almost spherical. By a second contraction, the squid now ejects from his siphon a stream of his black, inky secretion. He will usually make one or two or more contractions in an effort to escape, after which he becomes resigned. Not infrequently it happens that the luckless wight has not the squid unhooked before the inky discharge, and may have this sent at himself, since the siphon points away from the animal and upward. I have often seen a fellow struck full in the face by the inky stream, which event was invariably followed by a stream of almost as black abuse intended for the benefit of the squid.
The squid is unhooked by simply turning the jig upper end downward, when he readily drops off. For the most part they are caught wholly by the natives, the Americans usually preferring to look on or to find amusement ashore, though in some cases the fishermen themselves jig also. This, however, is apt to excite jealousy among the natives, or even such hostile feelings at times as to induce them to forcibly prevent the Gloucester men from catching their own bait, or even to purchase it in their harbor. The scene when the squid are thick is really exciting, the streams rising here and there, in twenty directions at once, point out the rapidity of the catch, and the monotonous noise of the squirt is only varied by an occasional murmur of discontent from this or that unfortunate as he lifts his querulous voice. In the dull time most of the jiggers drop away, leaving only those most long-suffering ones, but they return pell-mell if the frequent squirt shall indicate renewed activity.
The purchase of the squid is made at a certain price per hundred, this being usually thirty-five or forty cents, though occasionally falling as low as twenty-five cents. The price but rarely rises above forty cents, for the profits are too small to permit of its reaching a much higher figure. The number used by a single vessel in only two months is astounding. Our vessel, a small one, made three “baitings,” fishing each time about two weeks, and