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TWa Europea, differing only in the size of the leaves. Evelyn says in his “Sylva:”—“It is of all others the most proper and beautiful for walks, as producing an upright body, smooth and even bark, ample leaf, sweet blossom, the delight of bees, and a goodly shade at the distance of eighteen or twenty feet. Besides its unparalleled beauty for walks, its other perfections are—that it will grow in almost all gardens; that it lasts long; that it soon ... its scars; that it affects uprightness; that it resists a storm; that it seldom becomes hollow.”

The flowers, which are of a greenish-white colour, in loose panicled cymes, and come forth in June and July, are very abundant, and larger than those of most other timber-trees. Cowper has alluded to

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but these are far beyond our present enumeration. The honey obtained from the #: of the lime is said to be the finest in the world. The fruit of the linden-tree, when mixed with the flowers, produces a paste not unlike that of cocoa. Evelyn says, “the berries, reduced to powder, cure dysentery, and stop bleeding at the nose. The distilled water is good against the epilepsy, apoplexy, vertigo, trembling of the heart, and gravel.” Schröder recommends a mucilage of the bark for wounds; and adds that the juice of the leaves fixes colours, And to mention only one other use of this beautiful and valuable product of the vegetable kingdom:—

-- Smooth linden best obeys The carver's chisel; best his curious work Displays in all its nicest touches."

The hoary dwarf rock-rose grows on elevated rocks, and in mountainous pastures in Wales and in the north of England: its petals, inversely egg-shaped, and of a bright yellow colour, appear in May and June. The common rock-rose is a shrub, 5. in hilly pastures, on gravelly soil, which flowers in

uly and August. The white mountain rock-rose is a rare plant, sometimes found in Somersetshire and Devonshire.

Prent Agynia.

The entire-leaved poeony has stems about two feet high, simple, round, and smooth; flowers with crimson petals, almost four inches broad; and a knobbed root. It grows on islands o Severn, and flowers in May and June, but is not truly

The stem of the field larkspur is nearly two feet high, erect, leafy, and branched. It grows in corn-fields, and flowers in July. A good blue ink, it is said, may be obtained from the juice of the petals. Common wolf's-bane, or monk's-hood, is found in several o: in England, though not truly native, and flowers in une and July. The stem, which is erect andleafy, terminates in a cluster of dark-blue flowers. The common columbine, with its pendulous, purple flowers, #1. in June, grows in meadows, pastures, and thickets. It has an erect stem, two or three feet in height, five capsules of a cylindrical form, and five equal nectaries, situated alternately between the petals. Custivation frequently increases the number of these nectaries, and diminishes that of the 3. The blossoms of the wild plant are blue, but the garen exhibits them of various hues.

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and its stem has about tho middle, three dark, smooth, green leaves, very beautifully formed, having veinstinged with crimson. The flower, if bruised, will raise a blister on the skin; to cattle, it is poisonous. There are three other species of wild anemone, blooming during April and May, all beautiful in appearance, but all possessing very acrimonious, and some even poisonous, qualities. One, the pasque-flower anemone, grows in elevated open pastures, especially in chalky soils; the stalks are four or five inches high. The blossom, which is much larger than that of the wood anemone, is very silky, and of a delicate lilac colour. The lesser celandine, growing in shady places, and common in meadows, flowers in March, April, and May, with petals of a shining, golden yellow. Wordsworth thus expresses his feelings in reference to this humble plant :

“Pansies, lilies, kingcups, daisies,
Let them live upon their praises;
Long as there's a sun that sets,

Primroses wild have their glory; Long as there are violets, t They will have a place in story:

There's a flower that shall be mine,
*Tis the little celandine.

“See its varnish'd golden flowers
Peeping through the chilling showers.
Ere a leaf is on the bush,
In the time before the thrush
Has a thought about its nest,
Thou wilt come with half a call,
Spreading out thy glossy breast,
Like a careless Prodigal;
Telling tales about the sun,
When we’ve little warmth or none.

“Comfort have thee of thy merit,
Kindly, unassuming spirit 1
Careless of thy neighbourhood,
Thou dost show thy pleasant face
On the moor, and in the wood,
In the lane,—there's not a place,
Howsoever mean it be,
But 'tis good enough for thee.”

Of the crowfoots, there is a very large family, defying all present attempts at description. Among them are the buttercups, with which we are so familiar. There are two species of this plant, both very common in our fields and pastures, which the botanist can readily distinguish, while the difference is seldom noticed by the ordinary observer. The more common of the two, in the pastures near London, and near the seacoasts of Scotland, is the bulbous crowfoot, or buttercup, at once recognised on digging up the plant, from its having a bulbous root, somewhat like a leek or a small onion; while the acrid species, commonly called the upright meadow crowfoot, has a fibrous root, without any bulging. But without digging up the plants, the two sorts may be instantly distinguished by the calyx or cup, which supports the yellow petals of the blossom ; this cup having its five leaves upright or nearly so in the acrid sort, and bent downwards in the bulbous species. It is a common, but most erroneous opinion, that the fine yellow colour of butter in spring is owing to the cows feeding on the buttercups in the pastures, and hence the name borne by these flowers; while the slightest observation will show that they carefully avoid these plants. If we consider the probable intention of Divine Providence in rendering these poisonous plants so common, we infer that it may be to afford F. to the grasses, and other herbage eaten by cattle. or were the whole green sward of the field composed of nothing besides grass, it might be eaten so bare as to destroy the roots, and produce a serious scarcity of forage; whereas, by the mingling of the poisonous buttercups with the grass, the cattle are prevented from grubbing up the latter to so great an extent as to injure its subsequent productiveness as the season advances. This is a very interesting view of the ordinance of God; and might be illustrated by many similar facts. We add only, in concluding our present Lesson, that to the order of plants now under consideration, belongs that splendid cultivated flower, the magnolia,

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the third person singular: the corresponding parts in the plural, being made by the addition of the letter n. The second person singular is formed by adding to the root the letters test: the plural of the same person taking tet. The root is found by removing the letters en from the form of the present infinitive: thus, from toben (to praise), take on, and you get so 6, which is the root. The Present Participle is made by adding to the root the syllable ent; as, tob-Hent, praising. The Perfect Participle is produced by prefixing to the root the augment ge ($ 69. 2.4) and suffixing the letter t (sometimes et): thus, ge-Hc8+t, praised. The Perfect tense is formed by combining the perfect participle with the present indicative of the auxiliary a 6 cm or sein, to Have or to be: as, id babe gescht, I have praised. The Pluperfect is formed by combining the perfect participle with the imperfect of 5aten or scim: as, its batte gescht, I had praised. The First Future is formed by adding to the present of the infinitive, the present indicative of the auxiliary mer ben, to BEcoME: as, is mette schen, I shall praise. The Second Future is formed by adding to the perfect of the infinitive, the present indicative of the auxiliary met t ent as, ić) werte gescht baben, I shall have praised.

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OUR present lesson is to be on the nervous system, and is one of great importance. This system includes the brain, the spinal marrow, and the sympathetic ganglia," or those accumulations of nervous substance whose influence is confined more particularly to the tissues contained within the cavity of the body. For a long time, the brain was regarded as nothin

more than a larger development of the spinal marrow, j then the spinal marrow was held to be but a lengthening out of the brain. The fact is, that neither proceeds from the other;the two are merely connected, and form independent centres of nervous power. No parts of the living body have excited greater interest than the study of the brain and the nerves. Till the time of Sir Charles Bell, it was taken for granted, “that all parts of the nervous system had certain general properties belonging to them in common; so that all were considered alike in function. The brain, including the spinal marrow, was looked upon as a common store, from which certain powers—such as that of motion—were issued to the body, and into which others—such as sensation—were received, the nerves being regarded as the conductors; and, in conformity with that view, it was further supposed that any part of the brain, or any single nerve, had equal power with all the rest of bestowing the numerous properties commonly assigned to the nervous system.” This Sir Charles doubted. In his judgment, it was contrary to reason to suppose that two functions, so essentially distinct from each other as motion and sensation, could belong to the same nerve. For example:—I will to movemy hand;—this volition or willingness originates in the brain, and the force, whateveritis, acts upon the nerve, the nerve conveys it to the muscle, and the muscle so acted upon leads to the motion of the hand. In this instance, the power proceeds from within to without. But I prick my finger ;the impression is received by the nerve expanded in the skin of the finger, is conveyed by that nerve to the sensorium, or that part of the brain which is the seat of sensation, and the mind becomes conscious of pain. In this case, the course of the nervous agency is from without to within. The force which

* From the Greek word gagglion, swelling or increase,

causes muscular contraction, passes along a nerve in one direction; and that which causes sensation, in a contrary direction. The question is, can the same nerve perform both functions at once? It was after years of intense study and application that Sir Charles Bell answered this question. His idea is, that “the nerves of the body possess distinct and appropriate functions, corresponding with the parts of the brain and spinal marrow with which they are connected at their Roots; and when a nerve, which appears simple, is found to bestow more than one endowment, it is a sign that that nerve has more than one origin from the brain, and consists, in reality, of several nerves joined together.” He maintained that each nerve of sense is limited to receiving a distinct and appropriate impression:— that the nerve of vision can only give ideas of light and colour; the nerve of hearing, impressions of sound; the nerve of smelling, the perception of odours, and so on; and that these special properties depended on each of the nerves of sense having its root in a distinct portion of the brain, provided and adapted for receiving its own peculiar impression. To establish his theory, he took a nerve of the arm, and, tracing it from the arm towards its origin in the spinal marrow, he found that, as it approached that origin, it subdivided into two parts or roots; that one of these roots entered a division of nervous substance distinct from the other; that the root which passed to the posterior division of the spinal marrow had a ganglion or an accumulation of nervous substance upon it, and bestowed sensation alone; while the root which went to the anterior division gave motion alone. While the great fact was thus brought out that the nerves of sensation are distinct from those of motion, Dr. Marshall Hall laid claim to the discovery of another set of nerves, which he calls the Excito-MotoRy, and which have their root or origin in the true spinal marrow; whereas, according to his theory, the nerves of sensation and volition only run along the course of the spinal cord. These excitor nerves have peculiar excitabilities, and pursue their course principally from internal surfaces to the MEDULLA oblongATA, or termination of the true spinal marrow; while the motor nerves pursue a reflex course from that medulla to certain muscles. Hence their name. The nerves of sense may actspontaneously, but these are always excited. Besides these two grand divisions, there is a third distribution known by the name of the ganglionic or sympathetic nerves, which are peculiar to the viscera of the chest and abdomen." Let us try and simplify this a little. We have the spinal cord, the top of which is called THE MeDULLA oblongATA, or the spinal marrow lengthened in its upward course till it becomes united with the brain. In the brain we have the cerebRUM, or that portion of it which is situated in the front and top of the skull, and which is the seat of sensation. We have also the CEREBELLUM, or that portion which is situated in the back of the skull, which is divided into two lobes, and which is inseparable from the power of volition. The nerves arising from these two portions of the brain, and from the spinal marrow, are called cerebro-spINAL NEnves. They pass off from the whole length of the spinal cord, at intervals of about an inch from each other, and go in regular succession to the back of the head, the neck, the upper extremities, the whole trunk, and the lower extremities. Each of these nerves is composed of two roots; one for motion, and the other for sensation. In addition to these, there is the FIFTH cenebral NERVE, whose larger root confers sensation on all parts of the head not supplied by the superior spinal nerves; while its lesser root gives the power of action to those muscles which we employ in mastication or the chewing of our food. Then come the Excito-MotoRY NERVEs, which arise from the medulla oblongata, or true spinal marrow. The excitement passes from some internal surface to the medulla or marrow, and from thence the motive-power is conveyed to the muscles to be affected and moved. Lastly, comes THE syMPATHETIc systEM. This consists of ganglia, or accumulations of nervous substance, scattered

*Wiscera, from the Latin viscus, the bowels or entrails, but including the §. liver, and lungs. ABDomen is also from the Latin—and signifies the 7.

among the viscera of the abdomen, and intended to unite in sympathy those parts by which the various organic functions are performed; such as secretion, absorption, circulation, assimilation of the food, the growth and decay of the body, and so on. But this is a point which we leave for the present. Sir Charles Bell was of opinion, that there are certain nerves which pass off from a circumscribed central portion of the nervous system—the medulla oblongata—and diverge to different parts of the head, neck, throat, and chest—or those strutures which together form a mechanism for respiration—that such an arrangement is not to be found in the lowest animals, but would seem to be a gradual development in the animal kingdom, until in man it becomes the organ of Voice and Expression. These he named RESPIRAtoRY NERVEs. Of his numerous examples, we select the two following:— “Observe the condition of a man convulsed with laughter, and consider what are the organs or system of parts affected. He draws a full breath, and throws it out in interrupted, short, and audible cachinnations; the muscles of his throat, neck, and chest, are agitated; the diaphragm is especially convulsed. He holds his sides, and, from the violent agitation, he is incapable of a voluntary act. It is impossible to avoid the conclusion, that it is the respiratory organs and their muscles which are affected during the paroxysm of laughter. “There is no state of suffering from which we can so well infer the nature of the agitation of the frame as from hydrophobia. The patient being sensible of his condition; and calm, and aware of the experiment whichistobemade upon him by his physician when he calls for a glass of water, cannot resist theinfluence of the disease. Heshudders—his face assumes an expression of extreme horrorandalarm—convulsive gulpingstakeplace in his throat;-heflies to some o: and clings to the bedpost in an agony of suffocation. This I have witnessed in a powerful man. I have had the pain of seeing the disease in a girl of eighteen. The irritability of the skin being increased to an awful degree, so that the touch of her long hair falling on the naked body excited the paroxysms. These recurred with a sense of choking, with sudden and convulsive heavings of the chest, a shuddering, and catching of the muscles of breathing, and an appalling expression of suffering. The paroxysms in such a case becoming more frequent and severe, finally exhaust the powers of life. these convulsions, it is the nervous and muscular systems belonging to the natural function of respiration which are affected; and as they are also the organs of expression, the condition is seen, not only in the countenance, but in the throat and chest, to be that of extreme horror.” Connected with this nervous system we have a particular structure made up in part of small vesicles, and in part of minute fibres. The vesicles are found in masses, and mingle with the fibrous structure. These masses constitute nervous centres, being the organs in which it is supposed that the nervous force is generated, and from which that force is sent forth and distributed in the body. The fibres form the nerves or cords of communication, which connect the various nervous centres. They convey nervous force to the several parts of the body in which they are distributed, and transmit to the nervous centres those impressions which are made by external stimuli. These nerve-fibres are full of nervous matter, are arranged in parallel or interlacing bundles, and the whole nerve is enclosed in a sheath or tube, which is composed externally of a very delicate transparent membrane. ...Within this tube is a hollow cylinder, of a substance which differs from the matter that occupies the centre of the tube—the centre being occupied by a transparent substance, which is the essential component of the nervous fibre. The diameter of these little tubes is between growth and rooth part of an inch. It may, however, be as much as Tooth, and as little in some few instances as Tr}roth. They are larger in the nerve-trunks than in the brain. Now what is the purpose, design, or end of this grand nervous system . It may be that it has little to do with those operations or functions which go to make up the vegetative or organic life of the animal. For example:—it may have little to do with the reduction of food in the stomach, since that is a purely chemical operation produced by the solvent power of the gastric juice. It may have nothing more to do with the process of absorption, this being a purely vegetative operation, by which the nutritive materials are taken into the respective vessels:—nor with the process of assimilation, which is effected by each cell taking up into itself its own appropriate element: —nor with the circulation of the blood, since the contractions of the heart result from its own inherent powers, so as to continue these contractions after it has been completely detached from the body:-nor with the act of nutrition, since, as in the case of the embryo itself, every tissue draws from the circulating blood the materials for its continued growth and development, by incorporating these with its own substance:-nor with the process of secretion, since the separation of certain products from the blood, is effected by cells situated upon free surfaces:—nor with the interchangeofoxygen and carbonic acid in the function of respiration, which o: place between the external atmosphere and the venous blood when brought into mutual relation in the lungs:-nor with the function of reproduction, which is effected by the inherent powers of the parts concerned, at the expense of the materials supplied by the blood. Still, there must be in all animals various accessory changes which are requisite for their growth and development, and which can be secured only by the peculiar powers with which animals are endowed. Thus, to commence with digestion. Dr. Carpenter says:“This preliminary process, which the nature of the food of the plant renders unnecessary for its maintenance, can only be accomplished [in the animal] by the introduction of the food into a cavity or sac, in which it may be subunitted to the action of the solvent fluid. The operation of grasping and swallowing the food, whenever it is performed, is accomplished #. the agency of the nervous system; and if it be checked by the loss of nervous power, the digestive process must cease for want of material. So again, although interchange of gaseous ingredients between the atmosphere and the circulating fluid may take place with sufficient energy in plants and lower animals, through the mere exposure of the general surface to the atmosphere, yet we find that in all the higher animals, certain movements are requisite for the continual renewal of the air or water which are in contact with one side of the o surface, and of the blood which is in relation with the other—for the direction of which movements, a NERvous systEM is requisite. In the excretory processes, moreover, the removal of the effete matters from the body can only be accomplished, in the higher animals, by certain combined movements, the object of which is to take up the products that are separated by the action of the proper secreting cells, and to carry them to the exterior of the body, there to be set free; and those combined movements can only be effected by the agency of THE NERVous systEM. Lastly:-in the act of reproduction, the arrangement of the sexual organs in animals requires that a certain set of movements should be adapted to set free the germ from the body of the male, and convey it to the ovule of the female; and further, that the ovum should be expelled from the body of the latter in a state of more or less advanced development. For these movements, a special arrangement is made in the construction of THE NERVous systEM, and in the application of its peculiar powers.” This does not exhaust the purpose or end of the nervous system. But we must reserve other equally interesting and important facts for our next lesson.

QUESTIons Fok ExAMINATION.

What are the seats or centres of the nervous system * What is the relation of the brain and spinal marrow? Can motion and sensation belong to the same nerve? In what consisted Sir Charles Bell's discovery : To what discovery did Dr. Marshall Hall lay claim P What is meant by excito-motory nerves; and where must we look for their centre? Whence arise the nerves of sensation and volition? What do you mean by the ganglionic or sympathetic nerves? What is the office of the fifth cerebral ...}} Which nerves did Sir Charles Bell call respiratory, and why did he so name them? Of what is the nervous system made up 2 How do you distinguish between a vesicle and a fibre? By what is the substance of the nerve protected 2 What is the diameter of these sheath-tubes? What is the purpose or design of the nervous system?

In what way does it assist in the process of digestion, or secretion, or reproduction ?

Is there any physical peculiarity in man which is not found in the lowest animals?

Why has man been endowed with the organ of voice and the power of expression in so high a degree?

LESSONS IN ENGLISH.—No. X.

By John R. BEARD, D.D. PREFDKES (sontinued). De, of Latin origin, denoting motion downward, has, in combination, the following meanings, being modifications of its original import. r Down, as in decrease, develop (Lat. volvo, I roll); dethrone, to put down a king. “The question of dethroning or cashiering of kings will always be an extraordinary question of state, and wholly out of the law."—Burke, “French Revolution.” also, in debase (from de, and battre, Fr. to beat), which originally meant to lower in regard to material things; e.g., “King Edward the Third, in the sixteenth yearof his reign, proclaimed

that no man should sell wool-fels or leather under such a price, so that these staple commodities might not be debased.”—State Trials, 1606.

The application of the word debase to a moral influence is exemplified in this citation :“Sam. So let her go. God sent her to debaseme, And aggravate my folly, who committed To such a viper his most sacred trust Of secresie, my safety, and my life.” Milton, “Samson Agonistes.” 2. From, as in debar, to bar or keep from, to prevent. “His song was all a lamentable lay, Of great unkindness, and of usage hard, Of Cythia the lady of the sea, Which from her presence faultless him debarr'd."—Spenser. 3. Out, thoroughly, as in declare (de and clarus, Lat. clear), in which the prefix has the form of an intensive; to make clear, that is, by utterance. 4. Not, with a force like un in undo, reversing the sease; as, decompose, to do the opposite of composing, that is compounding; decollation (de and collum, Lat. the neck) un-necking, that is beheading, decorticate (de and cortex, Lat. bark), to strip off the bark; defame, &c. “Bless ye men that cursen you, preye ye for men that defamen you.”—Wiclif, “Test. Luke vi.” Deca, of Greek origin, meaning ten, is found in decade, a period of ten years; in decalogue (deca and logos, Gr. word, discourse), the ten words or commandments of God. Deca is found also in the Latin form of Decem, as in decemviri (decen and vir, a man), the Decemvirs. “By this time were the ambassadors returned with the Athenian lawes. And therefore the tribunes (at Rome) were so much the more earnest and urgent that once at length they would set on to describe and put down some lawes. And agreed it was that there should be created decemvirs above all appeale.”—Bolland, “Livy.” Demi, of Latin origin, in the forms demi, semi, hemi, a half, is found in demy, in semibrewe, and in hemisphere. “Thou wouldst make an absolute courtier, and the firm fixture of thy foot, would give an excellent motion to thy gait, in a semi-circled farthingale.”..—Shakspeare, "Merry Wives of Windsor." A farthingale is a hooped petticoat or gown. Dia, of Greek origin, through (so as to divide), is found in diameter, a measure through, from one side of the circle to the opposite; in diagonal (from dia and gonia, Gr, a corner or angle), a line drawn from corner to corner; in dialogue (from dia and logos, Gr. a discourse), &c. Par. How dost, fool? Ape. Dost dialogue with thy shadow? War. I speak not to thee."—Shakspeare, “Timon." Dia is abbreviated into di, as in dichotomy (from dia and temno, Gr. I cut), a twofold division, or class. “All things reported are reducible to this dichotomie: 1, the fountain

of invention; 2, the channell of relation.”—Fuller, "Worthies."

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