FLYING

COLUMN  , in military organization, an independent corps of troops usually composed of all arms, to which a particular task is assigned . It is almost always composed in the course of operations, out of the troops immediately available . Mobility being its raison d'etre, a flying column is when possible composed of picked men and horses accompanied with the barest minimum of baggage . The term is usually, though not necessarily, applied to forces under the strength of a brigade . The " mobile columns " employed by the British in the South African War of 1899-1902, were usually of the strength of two battalions of infantry, a battery of artillery, and a squadron of cavalry—almost exactly half that of a mixed brigade . Flying columns are mostly used in savage or guerrilla warfare . " FLYING DUTCHMAN," a spectre-ship popularly believed to haunt the waters around the Cape of Good Hope . The legend has several variants, but the commonest is that which declares that the captain of the vessel, Vanderdecken, was condemned for his blasphemy to sail round the cape for ever, unable to " make " a port . In the Dutch version the skipper is the ghost of the Dutch seaman Van Straaten . The appearance of the " Flying Dutch-man " is considered by sailors as ominous of disaster . The German legend makes one Herr Von Falkenberg the hero, and alleges that he is condemned to sail for ever around the North Sea, on a ship without helm or steersman, playing at dice for his soul with the devil . Sir Walter Scott says the " Flying Dutchman " was originally a vessel laden with bullion .

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murder was committed on board, and thereafter the plague broke out among the crew, which closed all ports to the ill-fated craft . The legend has been used by Wagner in his opera Der fliegende Hollander . FLYING-FISH, the name given to two different kinds of fish . The one (Dactylopterus) belongs to the gurnard family (Triglidae), and is more properly called flying gurnard; the other (Exocoetus) has been called flying herring, though more nearly allied to the gar-pike than to the herring . Some other fishes with long pectoral fins (Pterois) have been stated to be able to fly, but this has been proved to be incorrect . The flying gurnards are much less numerous than the Exocoeti with regard to individuals as well as species, there being only three or four species known of the former, whilst more than fifty have been described of the latter, which, besides, are found in numerous shoals of thousands . The Dactylopteri may be readily distinguished by a large bony head armed with spines, hard keeled scales, two dorsal fins, &c . The Exocoeti have thin, deciduous scales, only one dorsal fin, and the ventrals placed far backwards, below the middle of the body; some have long barbels at the chin . In both kinds the pectoral fins are greatly prolonged and enlarged, modified into an organ of flight, and in many species of Exocoetus the ventral fins are similarly enlarged, and evidently assist in the aerial evolutions of these fishes . Flying-fishes are found in the tropical and subtropical seas only, and it is a singular fact that the geographical distribution of the two kinds is nearly identical . Flying-fish are more frequently observed in rough weather and in a disturbed sea than during calms; they dart out of the water when pursued by their enemies or frightened by an approaching vessel, but frequently also without any apparent cause, as is also observed in many other fishes; and they rise without regard to the direction of the wind or waves . The fins are kept quietly distended, without any motion, except an occasional vibration caused by the air whenever the surface of the wing is parallel with the current of the wind .

Their flight is rapid, greatly exceeding that of a ship going ro m. an

hour, but gradually decreasing in velocity and not extending beyond a distance of 50o ft . Generally it is longer when the fishes fly against, than with or at an angle to, the wind . Any vertical or horizontal deviation from a straight line is not caused at the will of the fish, but by currents of the air; thus they retain a horizontally straight course when flying with or against the wind, but are carried towards the right or left whenever the direction of the wind is at an angle with that of their flight . However, it sometimes happens, that the fish during its flight immerses its caudal fin in the water, and by a stroke of its tail turns towards the right or left . In a calm the line of their flight is always also vertically straight or rather parabolic, like the course of a projectile, but it may become undulated in a rough sea, when they are flying against the course of the waves; they then frequently overtop each wave, being carried over it by the pressure of the disturbed air . Flying-fish often fall on board of vessels, but this never happens during a calm or from the lee side, but during a breeze only' and from the weather side . In day time they avoid a ship, flying away from it, but during the night when they are unable to see, they frequently fly against the weather board, where they are caught by the current of the air, and carried upwards to a height of 20 ft. above the surface of the water, whilst under ordinary circumstances they keep close to it . All these observations point clearly to the fact that any deflection from a straight course is due to external circumstances, and not to voluntary action on the part of the fish . A little Malacopterygian fish about 4 in. long has recently been discovered in West Africa which has the habits of a fresh-water flying-fish . It has been named Pantodon buchholzi . It has very large pectoral fins with a remarkable muscular process attached to the inner ray . It lives in fresh-water lakes and rivers in the Congo region, and has been caught in its flight above the water in a butterfly-net .

FLYING-

FOX, or, more correctly, Fox-BAT . The first name is applied by Europeans in India to the fruit-eating bats of the genus Pteropus, which contains more than half the family (Pteropidae) . This genus is confined to the tropical regions of the Eastern hemisphere and Australia . It comprises numerous species, a considerable proportion of which occur in the islands of the Malay Archipelago . The flying-foxes are the largest of the bats, the kalong of Java (Pteropus edulis) measuring about a foot in length, and having an expanse of wing-membrane measuring 5 ft. across . Flying-foxes are gregarious, nocturnal bats, suspending themselves during the day head-downwards by thousands from the branches of trees, where with their wings gathered about them, they bear some resemblance to huge shrivelled-up leaves or to clusters of some peculiar fruit . In Batchian, according to Wallace, they suspend themselves chiefly from the branches of dead trees, where they are easily caught or knocked down by sticks, the natives carrying them home in basketfuls . They are then cooked with abundance of spices, and " are really very good eating, something like hare." Towardsevening these bats bestir themselves, and fly off in companies to the village plantations, where they feed on all kinds of fruit, and so numerous and voracious are they that no garden crop has much chance of being gathered which is not specially protected from their attacks . The flying-fox of India (Pteropus medius) is a smaller species, but is found in great numbers wherever fruit is to be had in the Indian peninsula . FLYING-SQUIRREL, properly the name of such members of the squirrel-group of rodent mammals as have a parachute-like expansion of the skin of the flanks, with attachments to the limbs, by means of which they are able to take long flying-leaps from tree to tree . The parachute is supported by a cartilage attached to the wrist or carpus; in addition to the lateral membrane, there is a narrow one from the cheek along the front of each shoulder to the wrist, and in the larger species a third (interfemoral) connecting the hind-limbs with the base of the long tail . Of the two widely distributed genera, Pteromys includes the larger and Sciuro- pterus the smaller species .

The two differ in certain details of dentition, and in the greater development in the former of the parachute, especially the interfemoral portion, which in the latter is almost absent . In Pteromys the tail is cylindrical and comparatively thin, while in Sciuropterus it is broad,

flat and laterally expanded, so as to compensate for the absence of the interfemoral membrane by acting as a supplementary parachute . In general appearance flying-squirrels resemble ordinary squirrels, although they are even more beautifully col- oured . Their habits, food, &c., are also very similar to those of the true squirrels, except that they are more nocturnal, and are therefore less often seen . The Indian flying-squirrel (P. oral) leaps with its parachute extended from the higher branches of a tree, and descends first directly and then more and more obliquely, until the flight, gradually becoming slower, assumes a horizontal direction, and finally terminates in an ascent to the branch or trunk of the tree to which it was directed . The presence of these rodents at night is made known by their screaming cries . Sciuropterus is represented by S. vclucella in eastern Europe and northern Asia, and by a second species in North America, but the other species of this genus and all those of Pteromys are Indo-Malayan . A third genus, Eupetaurus, typified by a very large, long-haired, dark-grey species from the mountains to the north-west of Kashmir (Eu. cinereus), differs from all other members of the squirrel-family by its tall-crowned molar teeth . It has a total length of 37 in., of which 22 are taken up by the tail . In Africa the name of flying-squirrel is applied to the members of a very different family of rodents, the Anomaluridae, which are provided with a parachute . Since, however, this parachute is absent in some members of the family, the most distinctive character is the presence of a double row of spiny scales on the under surface of the tail, which apparently aid in climbing . The flying species are also distinguished from ordinary flying-squirrels by the circumstance that the additional bone serving for the support of the fore part of the flying-membrane rises Pigmy African Flying-Squirrel (Idiurus zenkeri) .

from the

elbow-joint instead of from the wrist . The family is represented by two flying genera, Anomalurus and Idiurus; the latter containing only one very minute species (shown in the cut) characterized by its small ears and elongated tail . Most of the species are West African . In habits these rodents appear to be very similar to the true flying-squirrels . The species without a parachute constitutes the genus Zenkerella, and looks very like an ordinary squirrel (see RODENTIA) .