The most usual size taken from the body of a shark, is from six to twelve inches. The Indian Remora is said to be found of the length of two or three feet; and even, according to a description quoted by Dr. Bloch, to extend to seven feet. The usual number of divisions on its shield is from twenty-two to twenty-four.
The power of adhesion is retained for a long time, by this fish, after decapitation. I detached one of them from the body of a shark, decapitated it, and then applying the sucking-plate to a smooth surface, found the power of adhesion remained, and it continued for the space of nearly twenty minutes. The body of the animal, after the removal of the head, displayed much muscular irritability on being touched, and the pectoral and ventral fins moved for a long time afterwards.
The pilot-fish, as I have before observed, (Gasterosteus ductor,) is usually seen in company with the shark, and with no other voracious fish; it is of a beautiful azure colour, girded around the body by broad bands of a very dark blue. I have seldom seen them larger than a foot in length, but in breadth some exceed others. They have never been taken when in company with the shark, but, on the capture of that voracious animal, they hover about him as long as he remains in the water; and a very short time after he has been hauled on board, they can sometimes be taken by a basket from the chains, as they swim at that time very superficially, and sometimes have been known (but rarely) to take bait.
On the 18th, in latitude 2° 20′ north, and longitude 25° 26′ west, we got the north-east trade, far to the northward, being north-north-east, moderate and fresh breezes,[93] and on the 7th of April, we lost the north-east trade in about 30° 31′ north, and longitude 44° 20′ west.
On the 1st of April, in latitude 23° 17′ north, and longitude 42° 50′ west, several tropic birds (Phaeton oethereus) were seen hovering over the ship; this was considered a very unusual circumstance, from the distance we then were from land. The longest distance these birds have been seen from land, has been stated to be three hundred miles, but by the observations at noon we were distant full one thousand miles from land; the nearest being the northernmost island of the Cape de Verd group. The distance at which birds supposed not to wander far from land, are sometimes seen, is surprising. Penguins have occasionally been met with several hundred miles from land, although they are commonly supposed not to wander from it any considerable distance. An intelligent lady informed me, that, during a voyage from England to Batavia, in the ship Orynthia, between the Cape and the latter place, a Penguin was shot, being rather more than a foot in length, and of a smooth slate colour over the body, with a white breast, (as well as can be recollected at a distant period,) the ship being then at a distance of eight hundred miles from the Marion or Crozette islands, with fine weather, nearly calm at the time. This occurred on the 22nd of October, 1831.
Captain Beechey also states, (Voyage to the Pacific and Beering’s Strait, 8vo. vol. i. p. 16,) which tends to confirm the above fact, that, “as we approached the Falkland Islands from Rio Janeiro, some Penguins were seen upon the water in latitude 47° south, at a distance of three hundred and forty miles from the nearest land; a fact which either proves the common opinion that this species never stray far from land to be in error, or that some unknown land exists in the vicinity.”
On the 31st of March, in latitude 22° north, and longitude 41° west, the Sargasso weed was first seen, a few pieces occasionally floating by the ship. That these plants are produced within the tropics, there can hardly be a question; but at what depth they vegetate is still involved in obscurity: neither is it clearly ascertained why the banks of weed should always occur in the same places. The supposition that they proceed with the Gulf Stream from the Gulf of Mexico—whence the original name of gulf weed—is now exploded. This weed is considered to extend between the eighteenth and twenty-second parallels of north latitude, and the twenty-fifth and fortieth meridians of west longitude.
Mr. Neill justly observes, that “the gulf stream would convey them rather to the banks of Newfoundland than to the latitudes in which they usually occur; and it could not in any case accumulate them to the south of the Azores.”[94]
Horsburgh, in his Directory, mentions the range of the weed, as being first seen in latitude 24° or 25° north, and extending as far as latitude 40° or 42° north, but I regard the limits of its range as depending much on the prevailing winds blowing strong for some time in a particular direction. On the 3rd of March, 1831, I first saw the weed in latitude 20° 12′ north, longitude 35° 39′ west. In latitude 24° 16′ north, and longitude 36° 55′ west, large quantities of it were passed, and in latitude 37° 53′ north, and longitude 35° 32′ west, we left it.