A Year at the Shore

by Philip Henry Gosse

THE BLADDER.

The colours of this curious creature are very vivid: the bladder, though in some parts transparent and colourless, and in some specimens almost entirely so, is in general painted with the richest blues and purples, mingled with green and crimson to some less extent; these all being, not as sometimes described, iridescent or changeable reflections, but positive colours, independent of the incidence of light, and, for the most part possessing great depth and fulness. The sail-like erectile membrane is transparent, tinted towards the edge with a lovely rose-pink hue, the colours arranged in a peculiar fringe-like manner.

When examined anatomically, the bladder is found to be composed of two walls of membrane, which are lined with cilia, and have between them the nutritive fluid which supplies the place of blood. Besides this, the double membrane is turned in, somewhat as the foot of a stocking is inverted, when ready for putting on; and thus there is a bladder within a bladder, both having double walls. The inner (pneumatocyst) is much smaller than the outer (pneumatophore); and the point where it is turned in is contracted to the almost imperceptible orifice that has been mentioned. The inner bladder sends up closed tubular folds into the crest, which, being invested by the membranous walls of the outer sac, give to the sail that appearance of vertical wrinkles which is conspicuous.

EFFECTS OF POISON.

Most formidable are the powers which reside in the long tentacles. Each of these is an excessively slender ribbon of contractile substance, connected at its base with a translucent bag, and carrying at short intervals throughout its length semi-rings of thread-cells (cnidæ), similar to those of our Sea-anemones, but of far more deadly virulence. Mr. Bennett, who, for the sake of science, ventured to test their powers, has left us a terrific account of his sufferings. “On one occasion,” he says, “I tried the experiment of its stinging powers upon myself, intentionally; when, on seizing it by the bladder portion, it raised the long cables by muscular contraction of the bands situated at the base of the feelers, and, entwining the slender appendages about my hand and finger, inflicted severe and peculiarly pungent pain, adhering most tenaciously at the same time, so as to be extremely difficult of removal. The stinging continued during the whole time that the minutest portion of the tentacula remained adherent to the skin. I soon found that the effects were not merely confined to the acute pungency inflicted, but produced a great degree of constitutional irritation: the pain extended upwards along the arm, increasing not only in extent but in severity, apparently acting along the course of the absorbents, and could only be compared to a severe rheumatic attack; the pulse was accelerated, and a feverish state of the whole system was produced; the muscles of the chest even were affected, the same distressing pain felt on taking a full respiration as obtains in a case of acute rheumatism. The secondary effects were very severe, continuing for nearly three-quarters of an hour; the duration of the pain being probably longer, in consequence of the time and delay occasioned by removing the exciting and virulent tentacula from the skin, as they adhered to it, by the aid of the stinging capsules, with an annoying degree of tenacity. On the whole being removed, the pain began gradually to abate; but during the day a peculiar numbness was felt, accompanied also by an increased temperature in the limb upon which the stings had been inflicted. For some hours afterwards the skin displayed white elevations or wheals on the parts stung, similar to those usually seen resulting from the poison of the stinging-nettle. The intensity of the pain depends in some degree upon the size and consequent power of the creature; and after it has been removed from the water for some time, the stinging property, although still continuing to act, is found to have perceptibly diminished. To remove the irritation, at first cold water was applied, but this, instead of alleviating, increased the evil: an application of vinegar relieved the unpleasant symptoms, and olive oil has produced a similar beneficial effect. I have observed that this irritative power is retained for some weeks after the death of the animal in the vesicles of the cables; and even linen cloth which had been used for wiping off the adhering tentacles, when touched, still retained the pungency, although it had lost the power of producing such violent constitutional irritation.”[124]

Among the tentacles there are seen many depending organs, which take somewhat the shape of a claret-bottle, with the mouth a little expanded. These are highly moveable, turning and bending themselves in various directions. They are termed polypites, and are the mouths and stomachs of the animal: taking-in and digesting food, much as the protrusile lips of an Anemone do. Mr. Bennett describes the Physalia as seizing and benumbing small fishes by means of the tentacles, which are alternately contracted to half-an-inch, and then shot out with amazing velocity to a length of several feet, and which drag the helpless and entangled prey to the sucker-like mouths, the stomach-cavities of which were filled while he looked-on, with atoms of the flesh absorbed.

Dr. Wallich thinks Mr. Bennett must have mistaken what he saw; because he has observed that in a great number of cases the Physalia is accompanied by small fishes, which play around and among the depending tentacles without molestation. He has in so many cases seen this, and even witnessed the actual contact of the fishes with the tentacles, with no inconvenience to the former, that he too hastily concludes that “the urticating organs are innocuous.” Surely the premises by no means warrant such an inference. There is no antagonism between the two series of facts witnessed by such excellent observers; the venomous virulence of these organs has been abundantly proved by many naturalists, myself among the number, and Mr. Bennett, to his cost, as narrated above. We have only to suppose that the injection of the poison is under the control of the Physalia’s will, and the impunity of the bold little fishes is sufficiently accounted for.

THE GULF-STREAM.

That wonderful river that flows with a well-defined course through the midst of the Atlantic,—the Gulf-stream,—brings on its warm waters many of the denizens of the tropical seas, and wafts them to the shores on which its waves impinge. Hence it is that so many of the proper pelagic creatures are from time to time observed on the coasts of Cornwall and Devon. The Portuguese man-of-war is among them, sometimes paying its visits in fleets; more commonly in single stranded hulks. Scarcely a season passes without one or more of these lovely strangers occurring in the vicinity of Torquay; and from one of these I took the opportunity of making the careful drawing with which I illustrate this paper.[125] The fishermen and similar persons who pick them up, always endeavour to make a harvest of their captures, not by the sale, but by the exhibition of them, sometimes carrying the specimen from door to door, sometimes erecting a temporary screen in some place of resort, exaggerating the rarity and value of the specimen outrageously. This summer (1862) I have known of three in this vicinity; and have heard of one at the Isle of Wight, in July, which forms the subject of a memoir and a coloured figure by Mr. Humphreys in the Intellectual Observer; also, a fleet of hundreds scattered over both sides of the same island in August, as recorded by Mr. Rogers in the Zoologist; and finally, one at Tenby in July, obtained by Mr. Hughes, and recorded in the last-named periodical.

Mr. Hughes in his account mentioned a circumstance as normal, which, being unknown to me, excited my curiosity. His specimen was accompanied by “its attendant satellites, two Velellæ.” In reply to my inquiries my friend gives me the following information:—“My authority for the association of Velella with Physalia is Jenkins, the collector at Tenby, who was attending me when they were found.