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exist, and there are, moreover, cross relations which it is im. sistent with animal organism. This consideration led to a fresh possible to represent by such a diagram ; but the reader may study of the so-called wheel-animalcules. It is almost needless gather from it some idea of the nature of the relations, and to remark that the separate cilia were too small for their motions how impossible it is to follow them in a continuous descrip- to be distinctly traced, otherwise the mistake could never have tion of the animal kingdom.

| occurred. It is now supposed that the successive action of the Obviously, if a writer were to pursue any one of the lines cilia gives rise to an optical illusion, by which the appearance indicated, describing in order the animals which successively of rotation is maintained, while the organ on which the cilia is come under his notice on that line, he would be led further situated remains stationary. This supposition is rendered almost and further from the other lines, and he must pursue his course a certainty by observing the same motion in those nearly-allied until he has arrived at the highest animal of the branch creatures, members of the same class, whose discs are not circular, which he has been ascending; and then, like an Alpine traveller but divided into lobes. In these species it could be seen that the who has gained the summit of a peak, he will have to look lobes did not participate in the revolutions. The way in which around at similar elevations, between which and his own posi- this optical illusion is effected will be best seen by reference tion there is no stepping-stone. Thus he must, of necessity, to the illustration (Fig. VII.). From this it may be seen that if retrace his steps to the lower level, from which another ascend the cilia are deflected from the perpendicular only in one direction, ing path takes its rise.

and that a number of these act together, so as to cross one Another course, the one we have adopted, is to break off another while the down-stroke is given, it will give rise to a whenever a gap in the series occurs, and look around to see number of dark points where the crossing occurs, which points, that we are not leaving behind us any group of animals of a by the successive action of each cilium in the series, will seem similar or lower grade of structure, and if we are in danger of to pass rapidly round the disc, while, since each returns to its doing so, to return at once to the description of the neglected erect position separately and slowly, the eye cannot trace their group. We are the more reconciled to this method of procedure, motion. This method of explanation is rendered more probable because the relations of the classes to one another are so far by the fact that these aquatic creatures are usually examined from being determined, that each independent author has a under the microscope by means of transmitted light, and hence different arrangement.

anything which cuts off the rays of light at a particular point It will be seen by the diagram that, while the classes Cælen. will catch the eye and be followed by it. terata, Echinodermata, Annelida, and Myriapoda seem to follow These cilia are found so very generally throughout the range of one another in a natural succession, leading up to the Insecta- the animal series—they are placed on sach different parts of anithat order which, of all others in the articulate sub-kingdom, mals, and applied to such different purposes—that it is as well is perhaps the highest and most wonderfully constituted—the to give some little time to the consideration of them. We have Rotatoria seem to start in a rather loose relationship with the already had occasion to mention them as covering the body of Protozoa, and to lead up towards the Crustacea, a class which, some Infusoria, and being applied to locomotion. They are as represented by its higher orders, is almost as complicated in also found on the inner (as well as the outer) wall of the Calenstructure as the Insecta, but whose lower orders are very much terata, and there cause a circulation of the fluid in the stomach. less organised. It would seem also as though the great sub. They are set on the combs of the Ctenophora, or bands on the kingdom of the Mollusca is connected to the Articulates through larvæ of the Echinodermata, and in these situations are swim. their lowest class, the Polyzoa, and the class which we now have ming organs. We mentioned them also as set on the tufts of to describe.

vessels called gills in the Annelids, and we shall find them again The Rotatoria were first classed with the Infusoria by Ehren on the plate-like gills of Lamellibranchiata, and in these positions berg. This classification was not to be wondered at, as all the they cause a change in the external water, and so subserve the rotary animals are microscopic, and they are obtained from function of respiration. In the human subject they cover the infusions of vegetable or animal substances in water. Their membrane of the nasal chambers, the trachea, and the tubes outward appearance is also not unlike the higher orders of the leading to the lungs, and are continually employed to bring up Protozoa, and they move about by the same means as many of the mucous which would else choke the passages. In all these these do-that is, by means of the vibrations of closely-set, fine, cases, and in a thousand more which might be mentioned, their short, delicate hairs, called cilia. These cilia are so named action, though applied to different purposes, is essentially the from the Latin cilium, " an eye-lash." As these are the very same. Their motion always creates an appearance of wares minute organs of animals of less than oth of an inch in length, moving along in one definite direction, and never returning. 15 it may be well conceived that the name ciiia has relation to the is very easy to attribute motion to ciliary action, and, of course, form, and not to the size of the organs. The cilia in the Rotatoria, if the action be capable of driving liquid over the surface, it is instead of being scattered all over the surface of the animal, as I also able to move the surface upon which the cilia are set, and in Paramecium (a Protozoon), or in the Turbellaria, are confined the animal with it when that animal floats in liquid ; but it is to flat, convex lobos, situated round or near the mouth, whose not an easy thing to explain the method of this action. Wher edges they fringe. When the animal fixes itself, the motion of we say that the circulation in sponges is maintained by the these lashes brings food to its mouth by causing currents of ciliated chambers, the cilia of which whip the water in one water to pass towards it; and when it relaxes its hold, then the direction, we are repeating what a multitude of writers have same motion causes it to progress through the water much in said before us, but we by no means explain the motion. If & the same way as a screw-steamer is propelled. Some of these switch be passed violently backwards and forwards through air animals have the lobes all united into one circular disc, and as or water, it creates a commotion, but it has no tendency to the motion of the cilia is so ordered as to cause the appearance move the air or water, or the hand which holds it, in any de of a number of successive waves, following one another round and finite direction. How, then, do these minute switches eu et round the circle, it was once thought that the disc was a kind of their purpose? Why does not the effect of the motion in one cogged wheel whirling rapidly about a fixed axle. Hence the direction exactly counterbalance the effect of the motion in the name Rotifera, or wheel-bearing animals, was given to them. other? The writer conceives the following to be the explana If this had been the right explanation of the motion, it would tion, for which the reader will be in some measure prepared by have furnished an instance of a locomotive apparatus met with the remarks already made on the ciliary action in the Rotatoris. nowhere else in the wholo animal kingdom. A little reflection Suppose we conceive of a number of upright rods set on a memconcerning this contrivance led some naturalists to doubt whether brane in a line corresponding to the line of the resulting water it really existed. Of course it is essential to the mechanical and moving in a direction at right angles to this, or in th device which we call a wheel that it should be entirely discon- direction of the waves caused by them. If one cilium or to nected with the axlo upon which it plays, otherwise it could act alone, being rapidly brought down, the liquid will be thrown not revolve; and yet it is essential that all animal structures, off from its sides to the right and left, the more obliquely especially to those employed in locomotive actions, that there proportion to the rapidity of its motion. It will make its ! should be an organic communication between them and the by splitting the fluid, which, being thrown off laterally:, organs of nutrition, by means of which liquids can be sent to finally unite behind it. But suppose the rods on each sido supply the waste caused by vital actions. This liquid must also this single rod are in motion in a parallel direction at tl

i direction at the same be sent in such a way as not to be lost or wasted in the transit. time, then it comes in contact, not with stagnant water, bu It would seem, then, that the mechanism of the wheel is incon with the conjoined stream thrown off by these, which furni

greater resistance than if it acted alone. The water thus im- | untouched the problem of how the cilia themselves are set in pinging on the central rod will be prevented from readily uniting motion. The cilia of the Rotatoria seem to differ from those behind the other two; so that the vacuum will be filled up, not of most other animals in being under the control of the will of by the water which has passed through the interstices of the the animal. line of rods, but by fresh water which flows in from behind. In When a better appreciation of the action of the ciliary fringes other words, when the cilium acts alone, the resistance it meets of these animals was attained, the name Rotifera (Wheel-bearing with is in proportion to the section of the rod itself; but when animalcules) was changed into Rotatoria, or rotary animals. it acts with its neighbours, the resistance is little short of being Under this name they have been examined, and other details proportional, not to the section of the several rods, but to them of their structure show them to be much more highly organised and the whole space which lies between them. This speculation than the simple Protozoa, which inhabit the same waters, feed seems to be confirmed by experiment; for if a sheet of wire upon similar food, and are moved by a like agency. They

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1. SCOLOPENDRA MORSITANS. II. GLOMERIS. III. JULUS. IV. ANTENNA AND EYES OF JULUS. V. UNDER SIDE OF A DOUBLE SEGMENT OF

JULUS, SHOWING THE LEGS ON ONE SIDE. VI. NOTOMATA CENTRURA. VII. SCHEME SHOWING THE NATURE OF THE ROTARY ILLUSION. Refs, to Nos. in Figs.-V. 1, spiracle. VI, 1, ciliated disc; 2, gizzard ; 3, stomach ; 4, water-vascular system; 5, ovum; 6, forceps.

ganze be passed rapidly enough through the water, it is resisted have a definite alimentary canal, complete from end to end, and in with almost as great force as if it were not perforated. When some this canal is of very complex structure. The animals are fine sand is thrown out of a balloon in rapid descent, it appears transparent, and admit of the examination of their internal to fly violently upward, although the resistance opposed by the organs while alive; and to aid in this examination, Ehrenberg atmosphere to each particle in relation to its weight is small placed some indigo, in an extremely fine state of division, into as compared to that offered by the balloon in proportion to its the water where they were. He had the satisfaction of seeing weight. According to this theory, then, a number of cilia are the little opaque particles moved by the ciliary currents, depressed in concert and so create a wave, and only rise slowly swallowed, and pass through the whole length of the alimenand separately after the wave has passed on, and so assume tary canal, and thus make it more distinct. Immediately below an erect posture ready to propel a fresh wave at a considerable the gullet, in some (as in the Notomata of our illustration), is distance from the one which preceded it. This conforms well | an enlarged chamber, furnished with a tooth apparatus, which to the appearance created by the cilia both when they are used from its internal position is called a gizzard. In the Notomata to pass liquid over their surface, and when they are employed the dental apparatus consists of two teeth, one situated on each as locomotive organs. This partial explanation leaves entirely side of a central fixed tooth, and playing upon it as the hammers

of two blacksmiths fall on an anvil. Below the gizzard is a invisible when one is looking down on to the back of the animal. globular or elongated stomach, which is succeeded in some The generative organs open on the under side of the fore-part species by a narrow intestine, but in the one before us ends at of the body, and it feeds on decaying wood. once in a cloaca, from which the exit is at the forked tail end. The other order has the Scolopendra for its type. The trans. of the animal. Round glands, supposed to represent the liver, verse section of this animal is of oblong form, and exhibits a empty themselves into the fore-part of the stomach. From the flattened structure; the broad, horny back and belly plates cloaca two winding ducts pass up, one on each side of these, and being joined to one another on each side by leathery side-pieces, doubtless represent the water-vascular system which introduces on which the limbs are set, and the breathing-holes open. The aërated water from the outside. On these ducts, fastened by jaws of this creature are most formidable, and a poison-bag short stalks, are some little button-like organs, which are kept within the body sends a very noxious secretion by a duct to the in rapid vibration; but their use is not known. The outer end of the fang. These creatures are carnivorous, and rapid wall of the animal is often of an inflexible or little flexible in their movements, and their generative organs open at the material, which may be called a shell. This preserves the end of the body, being in this respect, as in all others, more flask-shaped body in its ordinary dimensions, and gives origin to like the insects than the Julidæ. muscles which run to, and can retract into the shell, the disc at one end of the body, and also the forceps by which the animal

LESSONS IN GERMAN.-XXXIII. attaches itself at the other end. The hind-part of these creatures is usually divided into rings, which, together with the struc

SECTION LXIV.–VARIOUS IDIOMS (continued). ture of the stomach, show an approach to the Crustacean type. | Umhin (around there) is used only in connection with fönnen, as :

We must content ourselves with this short notice of the 3ch fonnte nidyt umbin, es ihm zu sagen, I could not (get) around, i.e., I Rotatoria, and leaving them, return to the next class, which could not help, or avoid, telling it to him. Ich habe nicht umbin follows directly to the Annelids in the upward direction.' 'If we gekonnt, et zu thun, I could not help doing it, I could not but do it. wished to give to a sea-worm the powers of living in the air, 1. Spazieren (to take a walk, to take an airing) signifies, in and walking on the earth with as little change in its outward union with geben, fahren, reiten, führen, to take a walk, to take the form as possible, we must, in the first place, replace its tufts air in a coach, to ride out, or take the air on horseback, to lead of bristles by limbs which are directed downwards towards the about, or on a walk; as : Eine Stunde des Tages aufgenommen, in earth. These limbs must have a hard point, to strike against welcher er seine Sdwester spazieren führt, sißt er beinahe immer an seinem and lay hold upon the unevennesses of the ground; and in order Screibtische und studirt, während sein jüngerer Bruter lieber spazieren geht, that the hold might be maintained while the body is being spazieren reitet, over in Gesellschaft einiger Freunte spazieren fährt, one hour moved over the point of support, the limb must be jointed. of the day excepted, in which he takes his sister for a walk, he Inflexible levers, with fixed points of application, necessitate is almost always sitting at his writing.desk and studying, while fixed solid and resisting fulcra and firm structure, from whence his younger brother prefers to go for a walk, to ride on horsethe muscles which wield them may originate. Now the class back, or to take a drive in company with a few friends. Myriapoda, the members of which live in the air, differs from 2. Thun (to do) is in some phrases used impersonally, as :that of the Annelids, as far as their outward appearance and 68 thut nichts, it does or effects nothing, i.e., it is no matter. G3 appendages are concerned, just in the way which these require thut Neth, it is necessary. ments indicate. The outer wall of the body is of a hard, horny l 3. Behüte and bewahre, or Gott behüte, Gott bewahre, are often used, substance, which, though not quite so inflexible as the mail in especially in conversation, to denote aversion, abhorrence, fear, which the insect is encased, is still vastly harder than the etc., and may commonly be rendered, "God forbid." integument of the worm. The limbs, also, are jointed levers.

VOCABULARY. Besides these advances in structure, the organs of perception

Arg, bad.

Sin'wenten (fic), to Tau'musgebirge, 1. the are better developed. The feelers stretch in front of the head,

Au& biltung, f. culti-l turn to.

Taunus mounand are long and jointed. The eyes differ from those of insects

vation, education. Intem', in that, while. tains, a mountain in being simple instead of compound; but there are many of them gathered into two clusters on each side of the head. It

Bebant'lung, f. treat. Ita'lien, n. Italy. range near the might well be predicted that life in the air would require

ment.

Kenntniß. f. know. Rhine. differences in the organs of respiration quite as marked as those

Beleidigen, to offend. ledge.

Umhin'fönnen. (Seo in the organs of relation. The tufts of vessels which served

Bemer'len, to observe. Nie tersinken, to sink above.) as gills to the worms, could not be floated out in the air so as

Bewei'sen, to prove. I down.

Unglaublich, incredito expose the contained fluid to its oxygen, and they would be

Bewerében (sich), to sue Ohn'mächtig, weak, ble. liable to be torn or bruised.

for.

swooning, fainting Hence respiration is carried on

Bersa'gen, to refuse.

Blid, m. look, glance. Panzern, to arm with Bor'fäßlid, intentionupon an entirely different plan, the air being introduced into the body, there to act on its fluid, instead of the fluids being

Brüsten (sich), to be a coat of mail. I ally. [room. taken to it. In the illustration, we have taken pains to exhibit

| proud, to show airs Platte, f. plate, crown Wand, f. wall (of a the openings in the sides or under the animal, by which the air

Curgast, m. guest (top).

Wenten, to turn. is received into the body; but we intend to leave the full

(under cure). Rennthier, n, reindeer. Wienshaftlicy, scien. description of these, and of the great system

Danfen, to thank. of air-vegsels

Schlitten, m sledge. I tifically. which is called the tracheal system, to be described when we

Entfliehen, to flee. i Sonell'igfcit, f. rapi. ' Zubringen, to spend, write of the class Insecta, in which it is more largely developed.

Entwen'ten, to purloin dity.

1 pass away. Another marked difference between the Myriapoda and the

Groß thun, to boast, Tatel, m. blame, cen- Zutriglich, advantageAnnelids is exhibited in the circulatory or blood system.

brag.

sure. This

I one, conducive to. system, instead of being an advance upon that of the worms,

RÉSUMÉ OF EXAMPLES. seems to be a degradation from it; for instead of a closed G8 ist eine vortreffliche Sache, feine It is an excellent affair to have circuit of vessels which convey the blood in a definite direction, Betürfʻnisse zu haben ; oter wenn no necessities; or, if one eamand never permit it to escape from their bounds, we have only man nun einmal midt imhin' not by any means avoid having a heart stretching along the back of the animal, divided into a fann, ci'nige zu haben, toch we': some, nevertheless, at least, longitudinal series of compartments by valves which allow the nigstens nicht mehr zu haben, als not to have more than 2: 23 blood to pass towards the head only, while it is received from man schlechterdings baben muß. absolutely obliged to have. the general cavity of the body by slits in the sides of these 68 thut freilich für den Au'genblic It causes pain, indeed, for the compartments. Only a few vessels are given off from the front wche, cine Züchtigung zu erhal'. moment, to receive a correopart of the heart to run to the head organs, and the blood ten, rie wir nicht vertient' haben; tion that we have not me. is left to find its way back to the heart, not by vessels, but by aber intem' wir uns unsrer Un rited; but while we rememsoaking through spaces left between the viscera.

schuld crin'nern, lernen wir schnell ber our innocence, we soon The class Myriapoda has been divided into two orders, each das Grlit'tene vergesi'en.

learn to forget what we have of which is typically represented in the engraving. The type

suffered. er order is the Julus. Its body is an almost perfect Indem' er aber also octach'te, flebe, While he thus thonght, how: ch ring of which it is composed boars on its under da erschien' ihm ein Engel.

ever, behold there appeared irs of feeble legs, which are so small as to be

an angel unto him,

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LESSONS IN MUSIC.-XII.

| from its pitch, but chiefly from its key-relationship. We agree

with the learned man and skilful teacher Dr. Bryce, of Belfast, RELATION OF NOTES, ETC.

in saying, “It is by no means intended to say that the power of 1. In pursuance of the plan of the last Lesson, while our distinguishing the absolute pitch of each note in the standard pupils are continuing their practice and study of the three chief

scale (not including the flats and sharps] with some approach to notes of the scale, we shall “revise” and enlarge our previons accuracy is unattainable; nor that, when attained, it is useless. Lessons in reference to those points which are capable of being

But it ought not to be the first thing attempted: first, because misunderstood, or need to be more fully explained. We must it is not essential either to the perception of melody and har. ask the patience of those pupils who have put themselves into mony, or to their execution; and, secondly, because it will be our hands, with all good faith, content to learn one thing at a acquired with far greater ease after the mind has learned to time, for we have to teach many who cannot understand us, I feel the relation of the notes of the scale to one another, whatbecause they have misunderstood music before. Docility--that ever the absolute pitch of the individual notes may be." ... anality so absolutely necessary to the student of any arranged | “It is this relation of the notes to one another which constitutes course of lessons, which develops truth step by step, leads from music. The (pitch] notes F, c', F1, A, C, B flat, A. G. form the known to the unknown, from the easy to the difficult is too | melody, not because they are (the pitch notes] F, C, , etc., but often forgotten; and, as Dr. Marx says, to punish him for because they are respectively. the 1st, 5th, 8th, 3rd, 5th, 4th, neglect of docility, the student loses all certainty of success. | 3rd, 2nd of a particular scale. The proof of this is, that the The “MOVABLE DOH," on account of the common misappre- very same melody is produced by any other notes which stand hension of the first foundations of musical truth, and the false in the same relation, as for example, by G, D, G', B, D, C, B, A, or teachings which are abroad, is a great difficulty with some of by D, A, D', F sharp, A, G, F sharp, E, which are the 1st, 5th, our pupils. One of them "proceeded very pleasantly as far as 8th, 3rd, 5th, 4th, 3rd, 2nd, in their respective scales, and by the fifth Exercise, in which the key-note (or DOH) is G. But no notes whatever that stand in a different relation." Some that he could not understand.” He says, “In the previous of our readers will understand these remarks better when they exercise the notes DOH, ME, SOH, are placed respectively below see this same phrase (essentially the same, though placed at the line and in the first and second spaces; but in the exercise I different heights in pitch) in the old notation. They will perhave mentioned. I find DOH on the second line. Why should | ceive that the sol-fa syllables, which, having taken their pitch there be that change in the position of the note? And how is from the key-note, represent thenceforth only relationship of it to be sounded ?" The last question is clearly answered in sound, remain the same in all three cases. And why should the note to Exercise 5—“Take a middle sound of your voice

they not? for the tune is essentially the same! for the key-note or DOH." In the previous exercises a low KEY F. sound had been taken for DOH. In the first case any middle sound, and in the second any low sound, would have answered the purpose. The reason of the change of DOH's position on the staff is, that the staff aims to represent to us height and :

d s : d' m :s If im Ir :-|| lowness of absolute pitch, as well as key-relationship; and as the foundation-note of key-relationship, which we call don, had KEY G. before been a low sound of the voice, and at the bottom of the "ladder of pitch," now that this governor of key-relationship (DOH) is to be at a middle pitch of voice, it is necessary that it should be placed higher on the staff.

:d ls : d'Im :s fimr : 2. Another correspondent states his difficulty thus :-" The key-note of one piece not being always the same [in pitch] as KEY D. that of another, we are not able to recognise, with the sol-fa syllables, the same sounds [in pitch] which we sing to them in other pieces. What I would ask, then, is, whether we are always to sing the same sounds [in pitch] to each syllable, or merely to guess the sound of the syllable by its position in

:dls : d' l m :s fiml r :-) relation to that immediately preceding ?” Decidedly, you are 4. Once more, let not our friends suppose, with the corre not to sing the sol-fa syllables to the same pitch-sounds in one spondent last named, that it is necessary to " guess" at the tune which they had in a previous tune, unless the key-note sound of the notes, because non is placed wherever the key(DOH) is the same pitch in both. For we use the syllables note is. If your poi were fixed, and were nothing but anto represent, to mind and ear, the key-relationship of notes. other name for the pitch-note c, as in the French method of And we use the well-known letters c', B, A, G, F, E, D, to repre- solfa-ing, then, indeed, you would have to “guess" at the sent their absolute pitch. We hope presently to show that this sound of the notes. For instance, when you saw RAY, you practice of ours is both the oldest and the best. But do not would have to “guess” which of the three RAYS (abovelet our friends suppose that upon any of the common plans of named) it was. But if, on the English plan of solfa-ing, you solfa-ing they can associate a distinct idea of pitch with each | make Dor the key-note, then RAY is always at one and the place on the staff. Take, for instance, the first place below the same interval from Doh, and always produces a corresponding staff. That place may be filled by any one of three perfectly mental effect. And, as it is by this relative position and mental distinct sounds, by D, by D sharp, or by D flat. Now you may effect that notes are most easily recognised and most correctly call these three sounds by the same name-RAY, for instance — sung, you will soon learn to know and to strike the right sound but they are three most distinguishable sounds still. M. Fetis, with a decision and accuracy perfectly unattainable on the other the well-known French writer on music, very truly observes, plan, and without any “guessing" at all. As Mr. Lowell that, "a sound cannot be altered or substituted for another Mason says, “Ours would be more properly called the 17without ceasing to exist: Do sharp is no longer do. It is a movable DOH," for it is immovably fixed as the key.note. mere error so to call it, and it is one of those errors which have The other sou is at all the parts of the scale by turns. tended to render music obscure.” Your syllable RAY, then, 5. We are anxious to carry the perfect satisfaction of our cannot possibly represent a distinct idea of pitch. It can only pupils along with us, and must therefore step aside a moment stand for an indistinct, or, at best, a threefold idea! Hence longer to prove to them, once for all, that the method of solfathe indecision of voice, common among those who pursue the ing with "the movable DOH”-especially as distinguis! fixed method of solfa-ing.

from the French method imported by Dr. Shuttleworth and 3. Neither let our friends imagine that, even if they could Mr. Hullah-is the oldest, is supported by the best authority, establish in their minds a fixed association of absolute pitch and is in itself the best for educational purposes. It seems with each place on tho staff, in learning to sing at sight, generally admitted that Guido Aretino, the monk of Arezzo, who it is the attainment chiefly to be sought. For, undoubtedly, in the eleventh century invented both the staff and the use we learn to recognise a note by the effect which it produces on of the sol-fa syllables, applied the syllable ut (for which DOH

Y, as was amply proved in our eighth lesson, the has since been substituted) to the key-note. (See the Musical

the mind arises not, except in a small degree, Histories of Dr. Barney and Sir J. Hawkins.) Morley, the

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