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THE BAT TRIBE.

HIS curious family presents at first sight such a remarkable peculiarity of form, that a person, having no previous acquaintance with its different members, might well hesitate whether to call them beasts or birds. This difficulty vanishes on a closer examination, which proves them to belong to the former class, their resemblance to a bird depending on an umbrella-like expansion of delicate membrane, stretched upon the bones of the fore extremities, which are greatly elongated, and widely separated from one another. These correspond to the wires or whalebones, so that, by merely opening and shutting its hands, as it were, this timid night-loving little animal can poise its body in the air as lightly as its feathered companions. Nor is this all: the whole surface of this soft, hairless membrane is endowed with so fine a sense of touch,

that the creature is enabled, with ease and certainty, to avoid obstacles in its flight, and this even in circumstances where vision is impossible, distinguishing them apparently by the mere rebound of the wave of air produced by the impulse of its wings. The large, shell-shaped ears, with which some species of bats are furnished, possess the same exquisite sensibility, and thus aid their movements in the feeble and uncertain light in which they ply the wing. The thumb is short, and ends in a claw, by which, "during the day, they hang suspended from the roofs of barns and castles; or they shelter beneath the murky other buildings, or in crevices of ruined canopy of caves, or the overhanging gloom of shaded rocks. Neither do they despise the secure concealment afforded by the hollow chambers of ancient forest trees;"

but

"When fades the glimm'ring landscape on the sight,

And all the air a solemn stillness holds,"

they wake into life and activity, and may often be glimpsed in the dusk of a summer's evening, flitting to and fro in pursuit of the insects on which they feed.

The body of the smaller species of bat is very like that of the mouse, and about the same size. Like that, it is also covered with a close, soft fur. This resemblance has given rise to its popular name

of flitter-mouse. The membranous web, before described as extended upon the slender bones of the arms and fingers, collapses or folds together when these are retracted. It passes from the fore-limbs completely round the body, including the hind-legs, the feet of which are furnished with five claws, and also the tail, where one exists.

The Kalongs, or fox-bats of Java, are remarkable for inhabiting trees, to the branches of which they attach themselves

in vast numbers, and, hanging suspended by their hind-claws, with their wings wrapped round them, the silent and motionless groups are often mistaken for fruit amid the foliage. If alarmed, they utter piercing shrieks and cries, struggling at the same time to extricate their sharp claws from the branches, to which they cling so firmly, that, if shot while sleeping away the sultry hours, they retain their hold even after death. But at the approach of nightfall they relax their grasp, and one

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after another, in irregular but uninterrupted succession, they drop from the tree, and wing their steady flight for the nearest forest or plantation, where they do incredible mischief, by devouring indiscriminately every kind of fruit they can light upon. The Vampire bat is met with only in South America, and is said to equal a magpie in size. It has acquired an unenviable notoriety from its habit of sucking blood. This it is enabled to do by the peculiar form of its mouth, which is beset with tubercles, and contains a tongue "six times longer than broad, flattish above, rounded beneath, the surface slightly shagreened, with a peculiar cavity close to its extremity, the center of which is marked by a raised point, and the circumference by eight warts." Travelers vary in their accounts respecting its bloodthirsty propensity, which some affirm, while others deny.

Clinging to the branch of a tree in the Molucca Islands, there may be often seen a strange, grotesque-looking object, about a foot in length, with apparently shapeless and ill-matched limbs. It belongs to the tribe of lemurs, but, like the bats, which in some respects it resembles, its period of activity is during the darkness of night. Through the day it hangs suspended amid the branches of some lofty tree, often with its head downward; but, when darkness

sets in, it roams about the woods, preying upon fruits and insects. To give it the advantage of passing quickly from tree to tree, without descending to the ground, the skin on each side of its body is spread out in the form of a large web or mantle; and, in its springs and leaps, this, being suddenly spread out like a parachute, breaks the force of its descent, and enables it to alight in safety. On the ground these little creatures run with some degree of swiftness, and climb the trees in the same manner as a cat. They prove troublesome neighbors to the birds, on whose eggs they sup; nor have they any scruples in including the birds themselves in the repast.

Its color is usually red or gray, varying with its age. The ears are short and rounded, and the muzzle pointed, giving its head an appearance not unlike a fox. There seems something disproportioned in its small head, flat incurvated tail, slender body, and large bony limbs. The muscular development of the limbs, especially of the arms, is extraordinary; but, powerful as they seem, they are evidently unsuited to defend itself from attack, or to retain a firm hold of struggling prey; for the feet are undivided into toes, and the claws diverge in different directions. But these strong arms, though of little use against its enemies, enable it to climb

A BATTLE-FIELD.

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the trees, or to hang on the branch to which it clings for hours without fatigue. Two young are generally produced at a birth, for which the pendent body of the parent forms an admirable cradle. The membrane, by means of which they flit from tree to tree, is covered with short, close-set hair, which distinguishes them at once from the bats, in whom this membrane is always bare.

TH

A BATTLE-FIELD.

HE grouping of falling men and horses; the many heaped-up masses of dead moved strangely by the living-maimed among them, showing the points where the deadly strife had been the most severe; the commingling of uniforms of friends and foes, as both lie scattered on the ground on which they fell; the groups surrounding this and that individual sufferer, hearing his last words, giving to him the last drops of water which will ever moisten his lips upon earth. The stretchers, borne from various points, each carrying some officer or private soldier. . .

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still dreaming of the charge in which he
met his wound, and the thoughts of home
that flashed upon the heart as it seemed to
commit that heart to a moment's oblivion
of all else. Then comes the first dawn
of the hope that life may be spared; the
view of horrid objects passed-hope of
life growing stronger, but with it now the
dread of some operation to be undergone-
the sound of guns still heard, begetting a
feverish, impatient desire to know the re-
sult of the battle. Again, a partial waking
up at the voice of the surgeon; he and
his attendants seen as through a mist; the
deafened feelings causing all to seem as
though they spoke in whispers; the still
further rousing of the mind as the cordial
administered begins to take effect; the
voice of a comrade or friend lying close
by, himself wounded, yet speaking to
cheer; the operation borne bravely, and
felt the less, as it gives promise of a life
just now seemingly lost to hope; through
it all, fresh news ever arriving from amid
the din of the strife still raging-all this
has a life, and motion, and spirit in it
which mocks the real grave horror of the

scene.

A

SNOW-CRYSTALS.

MID the severity of the weather during the last January and February, the multiplicity of snow-crystals which fell with the snow-showers and storms attracted very considerable attention in England. It may be interesting to describe briefly the results of observations on this remarkable feature of the snow-fall of the present year. These crystals fell in great numbers, at intervals, from the last week in January to the middle of February, and were of very general distribution. On some occasions they fell in showers, unaccompanied by snow, presenting the phenomenon of little feathery tufts, sufficiently large to be discernible to the casual observer as they lay on the ground in clusters of a dozen to twenty in a group.

On examining these figures separately, even without the aid of a glass, their primitive form was easily determined to be that of a hexedral or six-rayed star; and this will be found to be the base of every crystal, however complex may have been its structure.

The light feathery forms of snow will doubtless be most familiar to our readers, as being the most common and easily distinguished. To the unassisted eye they appear to be sixrayed stars, feathered, at an angle of 600, with delicate and shorter rays, and with a nucleus or center of opaque and intense white. When viewed through a glass of even very moderate power they appear composed of minute molecules of snow, and exhibit a very imperfect degree of crystallization. As they fall together in little tufts, and the rays or spiculæ composing them are very fine, they resemble, as they rest upon the soil, the ravelings of soft white cotton, knotted here and there, the knots being represented by the large white

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molecule, the nucleus of each figure. When so spread over the surface of the ground they have a very beautiful effect. At about the same temperature, and mixed with those described, are crystals of an arborescent form, which are somewhat smaller, less opaque, but more complex in structure than the others. These are to be seen at a less distance from the eye, and as received upon a dark surface, and exhibit with great perfection and delicacy minute representations of leaves and branches, many of which may be compared to the beautiful pinnæ of the lady fern. When viewed through a magnifying glass, they are found likewise to be composed of minute molecules of snow. It is doubtful whether microscopic examination reveals additional beauties in this order of snow-crystals-it serves rather to reveal the deficiency of crystalline formation which has sent them down, in the character of an intermediate formation between the flake of snow and the more perfect order of crystals of which we will now speak. Many of these are very minute, and are chiefly to be distinguished by their glistening like particles of glass, and may be briefly divided into three classes. The first and least regular of these are arborescent, with six radii, and evidently of the same order of formation with the last, but more highly crystallized, and these have no other nucleus than the crossing and recrossing of the spicule. They are exceedingly beautiful, whether as exhibited to the eye or viewed through a lens; through the center of each leaflet (to borrow a word from the botanist) runs a delicate spike, which serves as an attachment to the primary rays. The rounding of the leaves is very perfect; but their arrangement and relative position is not always regular, at the same time they are invariably placed at an angle of 60°. But the highest order of crystals is that in which curved lines are exchanged for planes and angles; and the entire figure, by the aid of a high power, may be resolved into a combination of prisms, or set upon and around a primitive arrangement of radii.

An English scientific gentleman writes that on the morning of February 8th last, with a temperature of from 29° to 310 throughout the day, an immense number of very complex and perfect crystals were to be observed. On this morning thin VOL. VII.-28

plates of ice, of hexagonal form, fell in abundance. From eight to nine o'clock A. M. they were in nearly equal numbers with the snow-flakes, which drifted down with great rapidity. From nine to ten A. M. a remarkable variation in their figure was to be observed. The plain hexagonal figure became the nucleus of an order of forms composed of prisms, arranged around the six angles of the original figure; and on this morning, for the first time, I observed a series of inner markings within the crystals, which betokened a high degree of crystallization, and which I had only previously observed in the drawings of Dr. Scoresby of the crystals seen by him in the Arctic seas. Up to midday I observed a large variety of combinations-the difference chiefly consisting in the different forms of the prisms, their method of grouping, and the number and arrangement of the inner markings. From noon to half-past twelve I made drawings of a few specimens, in which the most complex of the figures I have described served as the nucleus of an arrangement of a far higher and more complex order than commonly to be observed; from the nucleus diverged spiculæ, clubbed at the extreme end with an elongated prism, while on either side of the spicule were arranged prisms at an angle of 600, resembling in their disposition the pinnæ of a fern. Within each prism were duplex and triplex markings of great delicacy, which communicated to the specimens, as viewed through a lens of high power, an exquisite degree of finish. Intermediate between the six spiculæ, so laden, were six other rays clubbed with prisms. In one variety I observed these were elongated to very graceful proportions, while in another they were clubbed to almost an oval figure. In one specimen that came beneath my careful observation, two of the spiculæ considerably exceeded the remainder in length, and remains an exception to my experience. From twelve till toward four o'clock P. M. the number of crystals much diminished; but the snow during the interval fell faster and more thickly, and at four was drifting in all directions, and was a storm. About this time the crystals commenced falling in greater numbers, but their character was altered; the six-sided figures of the morning had almost disappeared, and were exchanged for those of arborescent form, highly

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