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mature puss sneaks round the chickencoop, or prowls in the larder, its air and motions betray all the guile of her nature. In the veteran mouser, it varies as content or passion bears sway. Purring in your lap, puss waves coquettishly her tail, or droops it in drowsy satisfaction. But the same tail, when its proprietor is cornered by your terrier, becomes a thick club on which each particular hair doth stand on end, as if electrified with anger.

In significance of feeling, however, all tails yield to that of the dog. Endless in its variety-from the sweeping

train of the Newfoundlander to the long, naked whip of the greyhound, or the stiff wisp of the terrier-its express

ive curves and motions ever harmonize with its owner's feelings, and go through

a whole gamut of higher and lower pitch of spirits, from the brisk, animated flourish of the setter, as the gun is taken a-field, to the miserable droop or reversed curve of the beaten hound. But our readers in every country locality will find living illustrations worthy of study, in every street, and will discover hardly any two canine extremities alike, or any one which presents the same character and expression for five minutes together.

Among the families of birds, every child will select the peacock as the glorified examplar of ornamental tail. Nothing, certainly, can be more splendid than this gorgeous circle of green and gold; but it is not really what it is called, but a train of long feathers growing from the back, the real tail being beneath, and serving only as a support to this overshadowing splendor. The kindred tribes of pheasants and turkeys, however, display a similar, though plainer, show, which is made of the true tail-feathers. The bird of paradise, the widow-finch, the domestic cock, and many other examples may be readily called to mind, showing how far both the grace of form and beauty of plumage of birds are dependent on this part of their organization.

Enough of tails in their ornamental and expressive aspect; let us turn to their practical use, and look at the part they play in the animal economy. In this, some caution is necessary, lest we adopt some of the romantic fictions which have found their way into grave treatises of natural history; some of which may have so much of color of truth as to make the separation of fact and falsehood as difficult as was the task of Niebuhr, in deciding on the credibility of early Roman history.

We may, in the exercise of this discrimination, reject the story, how the fox makes of his tail an angling-rod and line, though it be told circumstantially, and on the authority of a bishop-the learned Pontoppidan, of Norway. He narrates how Reynard places himself on a stone, at the water's edge, on a fiord, and drops his bushy tail in the shallow brine. To it are attracted the crabs which prowl among the pebbles and sea-weed, and, as they fasten their claws in its hair, the cunning animal, by a sudden reversal of his position, casts them out upon dry land, and makes of them a capital breakfast.

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Another narrative, which originated with Dampier, and has the sanction of many repetitions, we may brand as untrustworthy, while we tell it for its excellence as an invention: When certain monkeys of South America come, in their woodland migrations, to a river too wide to be taken at a leap, they seek a point where two tall trees stand on the opposite banks. Round the overhanging bough of one, the stoutest monkey coils his tail, and thereby pendant, head downward, grasps in his paws the tail of monkey number two. The lat

ter does the same by number three, and so on, until a pendant chain of two or three dozen is formed, when they begin to swing in longer and longer sweeps, until the final monkey can catch, when at the end of his arc of motion, a projecting limb of the opposito tree. Then he climbs up until he has a good point d'appui, and monkey number one, letting go his hold on the opposite tree, the chain swings across, and all scramble up each other in reversed order, and go on their way merrily.

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The only known method of escape was in taking refuge behind a tree, which the serpent would sometimes, in its blind fury, transfix-the result being inevitably the death both of the tree and its assailant.

We should also, at least, suspend giving full credence to the story how the rat makes of his wiry appendix, on special occasions, a draught-chain or tow-line. Yet we are assured that once, in Scotland, a thrifty laird, finding his store of eggs to diminish, watched to see how the thieves could carry them away. He saw three rats go together to the pile of eggs, when, one turning on his back, the others rolled an egg upon him, which he clasped safely to his bosom, and his companions, taking his tail carefully in their mouths, started off as a team drawing a sledge, disappearing behind some barrels which were the outer fortifications of their castle.

Another story of rats' tails is more credible, hovering on the verge between myth and sober verity. This time it was a Frenchman, whose oil wasted un

accountably, though the narrow neck of his flask had seemed a sufficient se

curity against depredation. By a course of espionage like that of the Scotchman before-mentioned, he detected the rats lowering their tails alternately into the flask, and drawing them up, covered with the luscious fluid, which each in turn offered to his friend.

Leaving the skirts of fable-land, we find enough uses of tails which are incontrovertible. The fish's tail is his propeller, by which the pike or the albicore darts like an arrow through the water, and the salmon ascends the fall. By its power the breaching whale throws his huge bulk of a hundred tons clear out from the brine, to fall in a surge and splash of foam, visible from the whaler's deck at five miles distance; and, by its powerful strokes, he, when struck by the harpoon, dashes off through the billows, ten knots an hour, drawing after him the boats filled with his persecutors, half drowned in spray. The swordfish attains by its use the velocity which has, in repeated instances, driven his blade through the copper and thick planking, deep into the ship's hold. The "propeller," as adapted to our vessels, is nothing but a fish's tail, applied (for mechanical convenience) with a rotary instead of a reciprocating motion-just as a man, not able easily to put under his railroad-engine a set of legs moving alternately, like his own, modifies the plan, and resorts to the contrivance of an indefinite number of legs radiating from an axle instead of a hip-joint, and, by rotating it, brings them down successively in front of each other, so that his machine walks or runs along very well.

We have before mentioned the peculiar arrangement of the tails of the old red-sandstone and carboniferous fishesan arrangement perpetuated, in our day, only in a few existing instances,.such as the sharks; though some others, such as the gar or bony pike, which have a nearly symmetrical tail when adult, have an unequal or "heterocercal" one while young-an arrangement which seems to show an analogy between the general progress of created forms, and the successive stages in life of the growing individual-of which, whoso would know more, let him subscribe to Agassiz's new work, and learn.

The forms of fishes' tails are adapted to the general form of their owners, and adapted for the attainment of greater or less speed. The cat-fish, and other

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sluggish swimmers have obtuse or which sweeps everything before it.

rounded tails. The swifter fishes, such

as the mackerel or shark, have the tail prolonged into pointed lobes, so that "the area of the surface of the tail is in the inverse ratio of the distance from its axis of motion-the figure which may be considered best adapted for great velocity of progression." So say the learned. And an entirely analogous feature may be perceived in the wings, which are the propelling organs of birds-the slow and heavy-flying kinds, like the gallinaceous tribe, having short and rounded wings, while those of swift and long-continued flight, as the swallows, gulls, and petrels, have long and pointed wings. Experiments, suggested by such observations, seem to show that pointed, instead of broad and rectangular, paddles, would give greater velocity to steamboats, were not their use practically inconvenient.

The lobster-like crustacea also make their tails instruments of progression, or rather, we should say, of retrogression, for they flap them violently forward under the body, and dart backward from the reaction of the stroke with an arrow-like velocity, surprising to those who, seeing these animals only on land, deem them sluggish in their

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movements.

The swimming reptiles also make the tail their main instrument of progression -at least, those which have tails of serviceable size. The marine lizards of the Galapagos or Encantadas (those rocky isles of which Melville has told our readers such a dreamy and yet truthful story), when they swim, fold their legs close to their sides, and move by lateral oscillations of the tail. So does the alligator-so does the iguana, when he takes the water-so swims the snake, when driven from the bank, converting almost his whole length into one laterally-moving propeller. This traditional enemy of our race is not, however, as a little girl of my acquaintance once remarked of a gartersnake, "all tail," but is distinctly separable into head, neck, and body, also; and anatomists have, in some species, detected even rudimentary legs.

The tail of the alligator and that of the shark, also, are, upon suitable occasions, convertible into offensive weapons of no small power; and, on their capture, it is advisable to secure or disable, as soon as possible, this powerful flail,

Perhaps it was of such instances that Milton had heard, when he wrote, in his hymn on the Nativity, how

"The old dragon, under ground,
In closer limits bound-
Not half so far casts his accustomed sway-
And, wroth to see his kingdom fail,
Swindges the scaly horror of his folded tail."

Here we see that the despised member is not quite unmentionable by writers of some standing. We might quote more from the same authority, of "Typhon huge, ending in snaky twine," or of the

"Serpent, standing on his rear, Circular base of rising folds, that towered, A surging maze-"

or from an older poem still-how Behemoth "moveth his tail like a cedar"-or many another allusion, were it necessary still further to dignify our subject. We trust, however, it is needless.

En passant from the reptilia, we may say that their tails are not incompetent of being made into musical instruments, whatever may be, according to the old adage, the impracticability of making such a use of the same member of the pig. We do not, however, mean a whistle, but only a set of castinets or bones. We call into court, as a witness, the rattlesnake, and the fact is demonstrated. And, before leaving the consideration of the tail as an offensive weapon, we will refer to the sting ray (trygon), which bears a sharp and serrated spine midway upon its tail, which can inflict a severe wound on its incautious captor. The virulent weapons

borne by scorpions and other insects, at their hinder extremities, are not properly to be cited as illustrations of our subject; for these spiteful appendages are only situated caudally-not tails in themselves and differing only in location from the similar and more deadly weapons borne by venomous serpents in their jaws, and by centipedes on one of their front pairs of feet.

Birds put their tails to more uses than one. Not to recur to their ornamental capacity, noticed in speaking of the peacock and pheasant, we may look at them in their guiding function, as rudders to steer the bird in its rapid flight. That they serve this purpose is undeniable; for, if the reader will do as we did once (we admit that it was in boyish mischief, and not in scientific investigation), and pull out a pigeon's terminal feathers, his uncertain and staggering flight will at once prove that he has lost a controlling member. In further proof of this, it may be remarked that, while birds of rapid and well-controlled flight-such as the falcons and swallows-have tails of very useful dimensions, the tribes which make no use of their wings have no tails of any consequence. Instances of this are seen in the penguins, grebes, and loons, among aquatic birds, and the struthious tribes among terrestrial forms. The ostrich, with its feeble wings, has but a tuft of soft plumes as a caudal ornament; the apteryx, in which the wings are merely rudimentary and only detected on close scrutiny, has no tail at all.

In some birds, the tail forms a sort of third limb or support, so that the bird is practically a tripod. So it is with the woodpecker, who holds tight to the tree with his claws, while his tailfeathers, brac

ed against the bark below, keep him from falling backward or slipping down, and support him most comfortably and conveniently in his erect position. If you examine his tail-feathers, you will find them worn

to sharp points

by friction; and the same is true of those of the chimney-swallow, who clings in the same manner to the rough sides of his native flue.

Among quadrupeds, the kangaroo seems to make use of his tail in an analogous way, as he sits erect and views the land around him. More than this, it has been reported that this member, which, with him, is very stout and muscular, aids very much in his flying leaps; and that, if deprived of its assistance, his bounds are awkward and much diminished in length. this, however, we will not be answerable.

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