Portugese Men-of-war

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TRANSACTIONS.

PORTUGUESE MEN-OF-WAR. BY

MAJOR COOPER ;

CHESTER DOUGHTY,

PHILIP LAVER, P h . D . ;

B.A.;

a n d D R . MARK TAYLOR.

WHEN I was a boy at school there I distinctly remember seeing lying on its side one, or possibly two, Portuguese Men-of-war (Physalia physalis, Linn.), with its balloon fully eight inches in height and about in diameter. This Jelly-fish of the order CCELENTERATA was on the shingle of the beach at Aldeburgh, half way to Thorpe ; and a man named Alexander, probably he who is referred to in Hele's 1870 Notes and Jottings about Aldeburgh, told me and my companion Mark Taylor not to meddle with them : writes Mr. Doughty.—As far as I can recollect, about half-a-dozen such Men-of-war were picked up on the beach and taken to Dr. Nicholas Fenwick Hele, M.R.C.S., the great local naturalist. Whether we found any later, I am not sure. My father, Dr. Taylor of Bocking in Essex, always ran a marine aquarium and, as he happened to be exhibiting objects of Natural Science at Braintree the next day, he telegraphed to Hele and I took the beasties home in wet seaweed: certainly two survived long enough to be shown to, among other savants, Dr. Laver of Colchester, who identified them, and Dr. J . E. Taylor of Ipswich. My recollection is that the animals were grey and very iridescent, six or eight inches in length by three in breadth having the tentacles short excepting one that was conspicuously elongate ; but what I remember most clearly are the very severe stings my father received when uncurling the elongate tentacle, though by that time the creatures were surely more than half dead. I think the date was after the school left Crespigny House in 1882-3 : adds


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Dr. Mark Taylor. But Mr. Doughty considers it more likely to have been during the latter year, since he himself left Aldeburgh at its close and before the school moved to Eaton House there.—I distinctly recall such a discovery of Portuguese Men-of-war having been made about that period, writes Dr. Laver in February 1930 ; though, through a long series of years, I havenever heard of similar Men-of-war having been discovered about Southwold, for they want warmer water than the North Sea normally affords, Major Cooper considers. No species of this genus in Suffolk has hitherto been put upon record. Physalia is one of the genera of the order Siphonophora, belonging to the class Hydromusae, which comprises half the Hydrozoa, one of the main groups of the Ccelenterata, having the body radially symmetrical around an axis which passes through the mouth ; all its animals are aquatic, and the great majority marine. The Siphonophora live in colonies floating pelagically near the sea's surface; in each colony a great number of individuals are present, which perform various functions and exhibit considerable diversity of form. Thus, in Physalia, the tentacles may be short and tubulär or may attain the length of several feet; usually they are branched, and each branch carries a battery of nematocysts. The colonies often consist of hermaphrodites, but the generative organs lie on the manubrium (Shipley's 1893 Zool. Invert. 58). In a general way, the body is a cylindrical bladder, dilated in the middle and bearing a fancied resemblance to the hull of a ship ; the colour is purple, shading off to blue. Beneath the vessel are a great number offleshytentacles, cylindrical and twisted, which hang down like tassels of blue silk ; the central members of this bunch emit fine movable contractile threads, depending many feet into the water. These threads are studded with starry pearls of indigo colour, which form borders and spirals and zigzags of an elegance hardly to be conceived (Hart's 1882 World of the Sea). Physalia pelagica, as P. physalis used to b in England, is an animal composed of a bladder-like substance, the familiar instance of which is that beautiful creature the Portuguese Man-of-war. The outline is elliptical with additional pear-shaped smaller protuberance at one end, bearing to the body somewhat the relation of a head. At what may be termed the neck of this additional bladder, where it is contracted, as well as at the other extremity of the main bladder, there is an orifice through which the animal has the power of contracting the bladders to force out the air within, and thus at once sink by the force of gravity. This species is just over six inches in length and, when mature upon the open sea, bright purple ; but it is a mere visitant to Britain (Naturalist 1852, p. 89).


PORTUGUESE MEN-OF-WAR.

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Physalia Caravilla, a foot in breadth, can roll up or extend its tentacles with astonishing rapidity to a length of eighteen or twenty feet. While swimming it drags them through the water like a net; and, as soon as they touch a fish or Cephalopod molluscan, they embrace the doomed creature with the swiftness of lightning, paralysing all resistance by means of their funnelshaped suckers' venomous secretion. Then, rolling together, they convey the senseless prey to the numerous mouths of the Compound animal and these, sucking like leeches, pump out its nutritious juices. In this manner the Physalia devours many a much larger Bonito (Pelamys sarda, Cuv.) or Flying-fish (Exoccetus volitans, Linn. : Hartwig's 1861, Sea and its Living Wonders). Hart figures Physalia Antarctica, which certainly resembles what Dr. Taylor remembers of the Aldeburgh specimens ; and refers to the severity of the sting of P. pelagica upon persons in the Antilles, adding that this pain results from a blue corrosive liquid of a syrupy consistence : " but I had hardly seized it when all its fibres seemed to clasp my hand, covering it with bird-lime ; and I had hardly feit it in all its freshness, cold to the touch, when it seemed as if I had plunged my arm up to the Shoulder into boiling oil: and this was accompanied by pains so stränge that I could scarcely prevent myself from shrieking." No more vivid picture is imaginable than that, given in Conan Doyles story of the "Lion's Mane," of the allied discomedusa named Cyanea capillata, Linn., which is there represented as actually killing a man by its sting : this fearsome beast occurs in the Aide at Orford, verb. sap.!

THREE-SPINED STICKLEBACK.—Dr. J . Travis Jenkins states in the Fishes of the British Isles of 1925 that the Three-spined Stickleback (Gasterosteus aculeatus, Linn.), usually found in fresh water, is equally at home in brackish water or in the sea where, however, it is rare so far as his experience goes ; and he refers to a specimen caught in a shrimp-trawl. On 8th April last I found a specimen in a draw-netter's refuse well on Gorleston beach, far from the harbour-mouth. The little fish was ' strong alive,' as we say in these parts.—C. G. DOUGHTY. [These Sticklebacks were swimming in some numbers in a very brackish ditch near Aldeburgh on lOth April, 1930; some of them we possess, preserved in formal in.—ED.]


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