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NOTES ON THE MONTH.

By a Naturalist.

AUGUST.

the blue slate mountains tower eighteen | of small birds, like linnets, were flying thousand feet, in sharp, detached groups about, and beautiful locusts jumping or pinnacles, covered neither with vege- among the bushes. At times, the sun tation nor snow, and exhibiting decay shone like an orb of fire, without the and barrenness in its most frightful as- least haze; the stars and planets with pect. Here was a Tartar village found, a brilliancy, only to be seen from such called Huns. Where the dell was nar- an elevation; and the part of the horowest, there was so little space for the rizon where the moon was expected to river that the road continued but for rise could scarcely be distinguished bea small distance on the same side; and fore the limb touched it; the atmosover this frightful torrent, the English phere sometimes exhibited the remarktravellers had repeatedly to cross on ably dark appearances witnessed in ropes, or sangas, loosely hung from rock polar latitudes." Vegetation and anito rock on either side. Messrs. Ger- mal life appear in far higher regions on rard, one while, picked their way upon the faces of these mountains toward the smooth surfaces of granite, sloping to north, than on the faces of the souththe raging torrent; at another time, the towards Tartary, than towards Hindosroute led among huge masses and an- tan.-Massie. gular blocks of rock, forming spacious caves, where sixty persons might rest: here the bank was composed of rough gravel, steeply inclined to the river; there the path was narrow, with precipices of five or six hundred feet below, whilst the naked towering peaks and mural rocks, rent in every direction, threatened the passenger with ruin from above. In some parts of the road, there were flights of steps, in others frame-work, or rude staircases, opening to the gulf below. In one instance, the passage consisted of six posts driven horizontally into clefts of the rocks, about twenty feet distant from each other, and secured by wedges. Upon this giddy frame, a staircase of fir spars was erected, of the rudest nature; twigs and slabs of stone only connected them together, no support on the outer side, which was deep, and overhung the terrific torrent of the Tidung, the rapid rolling and noise of which was enough to shake the stoutest nerves. Some of these passages had been swept away, and new ones had to be prepared on the spur of the moment for the British discoverers. From the confluence of the Tidung with the Sutlege, the town of Ribe has a charming appearance; yellow fields, extensive vineyards, groves of apricot, and large, well-built store houses, contrast with the neighbouring gigantic mountains." At Zinchin, sixteen thousand one hundred and thirtysix feet above the sea, where their progress was arrested by Chinese guards, the travellers observed about two hundred wild horses, sometimes feeding and sometimes galloping on the tops of the heights; eagles and kites were soaring into the deep blue ether; "large flocks

AUGUST was emphatically called barnmonth (Ann Monad) by our Saxon ancestors, because it is the season for reaping and gathering into barns. The harvest is already ripe for the sickle; and the pious observer, as he contemplates the waving sea of yellow corn, spreading wide around him, and holding out a goodly promise of "seed to the sower, and bread to the eater," will remember the assurance of the Almighty, that "while the earth remaineth, seed time and harvest, and cold and heat, and summer and winter, and day and night shall not cease," Gen. viii. 22. Thus has it been since that declaration of the Lord of the harvest; and through a long series of revolving years, nations, too often forgetful of the Author of all their benefits, have marked with anxiety the return of this season, but without one spark of gratitude to Him who has given to man "the kindly fruits of the earth," that he " 'may enjoy them." As we pass through these corn fields in our way to the shore, let us not forget the God of nature and of grace, who "giveth liberally," and who" eth the grass to grow for the cattle, and herb for the service of man: that he may bring forth food out of the earth," Psa. civ. 14.

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The harvest has already commenced; the reapers are at their labour, and the gleaners are picking up the scattered ears of corn, which the benevolent will not deny them. If he be a Christian,

to whom the produce of these fields is intrusted, he cannot deny them, for he will remember, and remember with no common feeling, the solemn injunction of God, to the Jewish husbandman; "And when ye reap the harvest of your land, thou shalt not wholly reap the corners of thy field, neither shalt thou gather the gleanings of thy harvest. And thou shalt not glean thy vineyard, neither shalt thou gather every grape of thy vineyard; thou shalt leave them for the poor and stranger: I am Lord your God," Lev. xix. 9, Who can forget Ruth gleaning in the fields of Boaz ?

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But come; the shore is our destination, and though wild flowers are blooming around us, and though the sky-blue corn flower, (Centaurea cyanus,) the scarlet pimpernel, (Anagallis arvensis,) and the corn sowthistle, (Sonchus arvensis,) with its large, golden corolla, which folds at noon; together with the yellow goat's beard, (Tragopogon pratensis,) and other wild plants now in bloom, and profusely scattered over the banks, and along the sides of the fields, of which the small bindweed (Convolvulus arvensis) is peculiarly graceful,-though these may make us linger, yet let us hasten on, the tide is retiring, and many a nook beneath the cliffs, many a little pool among the jutting rocks, which they enclose and overhang, shadowing the placid water, will present us with subjects of the highest interest.

Observe those floating masses of jelly; who would suppose that they were living animals! Here one is left on the shore; let us examine it: it is one of the medusæ, the blue gellyfish. The acritous* division of the animal kingdom comprehends, among others, a class of animals, termed acalephæ, (sea nettles,) so called from the stinging sensation which most of them produce on the hand or any part of the skin that comes in contact with them; and hence the title of urticæ marine (also meaning sea nettles,) given to them by the older naturalists. The acalephæ form several groups, and of these, one, the pulmonigrada (from pulmo, a lung, and gradior, to advance,) is represented by the medusæ, of which there are various species, popularly termed gelly fishes, or sea gelly.

* From two Greek words, a (a) not, and кpivo, (krino,) to perceive, in allusion to the absence of any apparent nerves in the composition of the animals included in this section.

The structure of the gelly fishes, or medusa, considering that they are living beings, and capable of certain voluntary movements, is most astonishing, when we reflect upon it; and proves to us how little we yet know of the recondite laws of organization. The present medusa, for example, which belongs to a section termed Rhizostoma, often attains to the weight of several pounds, measuring from a foot to two feet in the diameter of its umbrella-like surface; but if this animal be removed from the sea, and exposed to the sun and air, it seems to melt away, and it will be found that its ordinary bulk and weight are owing to the presence of sea water with which numberless filmy cellules are replete, and which drains off gradually in a clear unaltered state; in a short time, this fluid will entirely escape, and leave only a delicately fibrous, or rather filmy tissue, so inconsiderable in quantity, as to weigh but a few grains. This almost imperceptible tissue is then the solid matter of the animal, or rather the animal itself, which may be regarded as a maze of filmy cells, in which the sea water, by some mysterious process, becomes an efficient in the maintenance of the creature's vitality, and instrumental in the performance of the various functions connected with its economy.

The usual form assumed by the medusæ (see engraving) resembles very closely

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in the extreme, and appears to serve both for the purpose of aeration, and the absorption of aliment. In the rhizostoma, there is placed beneath the disc a pendent peduncle, or footstalk, which is divided into eight foliated laminæ, or processes, and each of these processes is found to contain numerous canals, opening on the external surface by minute absorbing orifices; these canals ultimately merge into four large trunks, communicating with a central cavity in the disc, which is the stomach, or digestive cavity. It is then by the absorption of fluid, containing myriads of animalcules, through the minute apertures of the foliated peduncle, (this fluid being conveyed to the stomach,) that the nutrition of the animal is provided for; hence its name rhizostoma, (from 'Pila, rhiza, a root, and oróμa, stoma, a mouth.)

The stomach, it may be observed, is a cavity of considerable size in the centre of the inferior surface of the disc, at its union with the peduncle, and it is either really or apparently divided into four compartments, by means of a filmy membrane; it is usually found to contain a yellowish and almost fluid pulpy matter, which is regarded as the digested aliment, destined to supply the demands of the system through which it circulates, traversing certain large tubes or vessels, which radiate from the stomach towards the circumference of the disc, subdividing into smaller branches, and forming numerous junctions with each other, so that upon the margin a complete mesh of tubes is established.

But besides these, there is a large circular canal (of which a trace is seen in the sketch) which runs round the disc, at a short distance from its margin, establishing a direct communication between the main radiating tubes, for the more free and unobstructed circulation of the nutritive material. This simple arrangement seems to combine in itself the digestive, the arterial, and the aërating organs of higher animals; the radiating tubes being in the place of arteries; while their delicate mesh or network, following the thin margin of the disc, and permeated by fluids, exposed, from the filmy nature of the tubes, to the action of the air contained in the water in which the animal floats, fulfils the office of a respiratory apparatus.

But besides the tubes already described, there is a cluster of tubular

bodies, having no external orifices, connected with the commencement of the radiating tubes: these are by some regarded as organs for the secretion of a fluid analogous to bile; that is, as biliary organs in their lowest stage of developement: but others, and among them Eschscholtz, consider that the rudiments of a biliary system are to be found in certain little glandular, or apparently glandular bodies, placed in depressions round the margin of the disc, and asserted, by the above-named writer, to communicate by means of very minute tubes with the nutritive canals. It is evident, however, that these are mere opinions, based upon no satisfactory foundation.

The disc of the rhizostoma, and of other medusæ, is an organ of locomotion, an apparatus for enabling the animal to float steadily on the surface. Gelatinous as is its texture, it is nevertheless capable of certain contractile movements; and these are essential to the swimming of the animal on the surface, for on suspending them it immediately sinks. The movements in question are an alternate contraction and expansion of the disc, resembling the partial opening and shutting of an umbrella, and are repeated with great regularity; about fifteen flapping, or contractile movements taking place every minute. If the surface be calm, this extraordinary animal can propel itself along in any direction, for it can strike the water obliquely; but it is generally seen floating in shoals, passively carried onwards by the wind or current. Such is the substance of all that is at present known respecting it. After a storm, great numbers may be often found dead on the beach; in a short time, however, they dry away, or are washed back into the sea by the next tide.

Observe that singular creature, slowly creeping at the bottom of a little basin in the rock, filled with clear sea water; and in which, until the tide returns, it is imprisoned, not because it cannot escape, but because it will not voluntarily leave its native element. It is a star fish, (the asterias rubens,) and belongs to the class echinodermata; let us take it out, and examine it more attentively. It consists of a central portion, or disclike body, from which five rays, capable of flexion and extension, branch out; its external covering is a horny, or coriaceous integument, with calcareous

portions thickly interspersed throughout | become distended, and pass through the

its texture, giving a roughness, or tuberculated structure to the surface, and forming spinous processes around the mouth and along the rays. The integument is tinted in various species with different colours; in the present with a red pigment, doubtless one of its secretions, as is also a reddish fluid which exudes from the surface of this starfish, and which is of a caustic nature, producing considerable irritation on the hands of persons who roughly grasp the animal.

ambulacral orifices; but on the expansion of the sac, the fluid leaves the tubes, which contract so as simultaneously to expel it, and are immediately withdrawn through their respective apertures. The sacs in question derive their fluid from a system of vessels distinct, according to most physiologists, from those of the arterial system; but whether the fluid is a peculiar secretion, or merely sea water, is a point not established.

The mouth of the asterias is seated on the under surface of the central disc, or body, and the osseous or calcareous portions around it give firmness to its margin, and perhaps act to a certain extent as teeth, or assist in the pre

The integument, horny as it is, is evidently sensitive and contractile, shrinking on the application of stimuli, or of the knife; it can readily change its form, the rays can be bent or extended, or turned in various directions, and these motions appear to depend on the pre-hension of food; it leads into a very sence of fibrous bands, extending along the covering of the rays, from the central body, or axis. Besides the investment described, and which protects the internal parts, each ray is farther supported by a sort of rudimentary skeleton, or calcareous framework, composed of a series of distinct portions, like the spinal column of vertebrated animals; these portions are fitted to each other, and united by ligament, so as to produce a succession of joints, extending down the under surface or floor of each ray, beginning from a circular framework of the same character which encloses the mouth. The arrangement of each of these portions, or plates, is such as to admit of certain little apertures, like pin holes, between them; and these apertures form four rows extending down each ray in a groove, which groove is termed the ambulacrum, or avenue, and the holes, are called ambulacral orifices.

Through these orifices the animal is capable of protruding small, fleshy suckers, or feet, (each terminating in a sucking disc,) which are the principal agents of locomotion, and also of securing the prey within the folds of the rays. The manner in which these suckers are protruded and withdrawn is very curious, and yet extremely simple: they are muscular and tubular, closed at their extremity by a disc; but internally they communicate each with a sac, or reservoir of fluid, itself being muscular and contractile. When the animal wishes to protrude these suckers, it contracts these sacs, forcing the fluid into the tubes, which thus

wide œsophagus, or gullet, longitudinally folded, and this expands into a capacious stomach, which, instead of being confined to the central portion or disc of the animal, is carried out by means of curiously convoluted or arborescent tubes, plaited on a delicate membrane, which both lines the external investment of the animal, and is reflected over all the internal organs. Each ray contains two of these arborescent prolongations of the stomach, the nature and use of which do not appear to be clearly understood, though they are probably destined, like the intestinal canal of higher animals, for absorption of the nutritive particles of the digested food, which is taken up by a system of veins, abundantly distributed like a fine net work over them, throughout their

course.

The great sac of the stomach is furnished at its base with a small biliary apparatus, opening into it by a free orifice, whence issues the bilious fluid. The veins collect into a large circular vessel, a sort of common trunk sweeping round the central disc, which communicates with another vascular tube encircling the mouth, by means of a large canal; this canal is highly irritable, and is probably analogous in its function to a heart; the oral circle being the commencement of the arterial system, whence vessels are distributed to every part of the system. Besides these vascular tubes, there is a calcareous tube, connected with the circular oval vessel, and called the sand canal, within which are two convoluted lamine of the same calcareous texture;

but of its use nothing positive is as- | protruded, and fixed tenaciously upon certained. The aeration of the circu- it; its efforts are in vain, and struggle lating fluids of the sea star is effected as it may, it is dragged closer and closer, by the free admission of sea water into and forced into the mouth, which closes the general cavity of the animal through over it. In a short time, all the soft multitudinous minute tubes which open parts of the prey are dissolved, the hard externally, protruding through pores, and shelly portions being rejected. Crabs upon the outer surface; through these and shell fish of a considerable size are the water passes into the membranous swallowed entire, for the stomach is cavity, and bathes all the viscera, its amazingly dilatable; but shell fish of oxygen acting upon the fluids circulating great size, as large oysters, etc. are not in their vessels. the less its victims, though it cannot swallow them whole.

The membrane which lines the horny covering, and that investing the viscera, are covered with multitudes of minute fibrils, or cilia, the continual action of which produces currents in the sea water absorbed; these cilia, however, are not limited to the general lining, or as it may be termed, peritoneal membrane, but are also distributed over the cavities of the suckers, or feet, over the inside of the stomach, and its prolongations, and over the external surface of the body. Of the purpose which these cilia serve in the economy of the asterias, a presumption only can be formed; it is, that they are agents in the aëration of the vital fluid, and by their action ensure a perpetual change in the water, so that every part may be supplied with it fresh, and unexhausted of air.

We might here enter into other minutiæ respecting the organization of these creatures; but enough has been said to show how wonderful their structure is, and how much yet remains to be investigated. A few words with regard to their habits and manners will not prove uninteresting. It may be observed, then, that they are highly carnivorous; they feed upon putrescent substances, and make shell fish, crustaceous animals, (as crabs,) and small fishes their prey; they are very voracious, and, though apparently inert, are capable of overpowering the struggles of the most active of their victims.

When watching for their prey, they rest with the rays gently bent towards the mouth; and these, when a crab or shell fish is within their range, are folded closely over it, drawing it towards the mouth, which is dilated to engulph it still, if active, it might escape, or, by dint of strength, force itself from the grasp of its deadly antagonist; but no, no sooner do the rays fold over it, than all the suckers, to the amount of more than three hundred in each ray, are

The destruction which the sea star commits among oysters was indeed well known to the ancients, who believed that it obtained the mollusk by inserting one of its rays between the valves of the shell, when the creature happened to lie with them partially open, and that it then gradually forced itself in, till its prey became in contact with its mouth. Though the fact of its destroying large shell fish is unquestionable, the mode by which it obtains the mollusk, shut up in its strongly closed shell, is not easy to be understood: certainly it is not by the method | which was supposed by the ancients.

Some degree of light, however, has been thrown on the subject, by M. Deslongchamps, (see Bullet: des Sciences de M. le Baron Ferussac, vol. x. p. 296,) who on one occasion saw on the shore (when the tide having retired, had left only a few inches of clear water on the sand) considerable numbers of this species, (Asterias rubens,) rolling about in compact balls, five or six being fastened together by the interlacement of their rays. Not a little astonished at this, he proceeded to examine these balls, and found that in the centre of these knots of star fishes, there was a large, bivalve mollusk, (Mactra stultorum, Linn.) grasped closely round by their united rays; the valves were partially open, the mouth of each asterias was in contact with their edge, while between the valves were introduced large rounded vesicles of a thin membranous texture, and filled with a transparent fluid.

On examining these vesicles more attentively, it was found that they were ranged round the mouth of the asterias, being attached by peduncles, and were five in number, but of unequal sizes, two being as large as filberts, the other three not larger than peas. At the extremity of each was an aperture, through

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