or sucker, which in some kinds can be drawn up and concealed in the mouth; it consists of a long channel, ending in 2 fleshy lips, and enclosing on its upper side from 2 to 6 fine bristles, sharp as needles, and making the punctures so familiarly known in the case of mosquito bites; as this apparatus takes the place of the jaws of other insects, these wounds may properly be called bites. The saliva which flows into the wounds causes the well-known swelling and itching, the irritation in some skins amounting to inflammation. The sheath serves to maintain the lancets in position, and the latter having made their punctures form a groove along which the vegetable or animal fluids rise by the suctorial power of the insect and the force of capillary attraction. In the flies which only lap their food the proboscis is large and fleshy. The antennæ in the gnats are long and many-jointed, in the flies short and thick, at the base of the proboscis. The wings are generally horizontal, delicate, with many simple veins in them; the posterior wings are metamorphosed into the balancers or poisers. Some entomologists, as Latreille, think the poisers do not correspond to posterior wings, but are vesicular appendages connected with the posterior respiratory trachea of the chest. Just behind the wing joints, and in front of the poisers, are 2 small convex scales, opening and shutting with the wings, and called winglets. The thorax is often the hardest part of the insect, composed principally of the intermediate mesothorax. The abdomen is not always united to the thorax by the whole of its posterior diameter, and in many females ends in a retractile jointed ovipositor by which the eggs are deposited. The legs, 6 in number, are usually long and slender, with 5 articulate tarsi and 2 claws at the end, beside 2 or 3 little cushion-like expansions, by means of which they are able to ascend the smoothest surfaces and to walk with the back downward with perfect security. According to Marcel de Serres, the dorsal vessel (the heart) in diptera is narrow and its pulsations frequent. Respiration in the adult is carried on by vesicular and tubular trachea. The nervous system consists of an aggregate of cerebral ganglia, and in some of 9 other ganglia, 3 in the thorax and 6 in the abdomen, connected by longitudinal simple commissures or cords; the larvæ have usually one more pair of ganglia than the adults, and have the commissures often double. The proboscis being the transformed under lip, often geniculate, the perforating bristles may be regarded as maxillæ, mandibles, and tongue. In those larvæ which have a distinct head, as in the mosquito, the jaws are arranged for mastication, though some of the pieces are wanting; but in the acephalous maggots the mouth is suctorial. Communicating with the gullet is a thin-walled vesicle, the sucking stomach, in which the fluids swallowed are temporarily deposited; the stomach proper is long and narrow, and makes many convolutions in the abdomen. The end of the intestine is short,

muscular, and pyriform. The uriniferous vessels are long, and generally 4 in number, opening into the lower extremity of the stomach; the ovaries consist usnally of numerous short 3 or 4-chambered tubes, terminating in a short or a convoluted oviduct; the testicles are 2, simple, and generally of an oval or pyriform shape, with long vasa deferentia ending in the ejaculatory duct in common with 2 simple accessory mucous glands, and with horny valves enveloping the projecting copulatory organ. The larvae, or maggots, are without legs, generally whitish, and vary exceedingly in form and habits; the larvæ of the mosquito are aquatic, breathing with the head downward through the tubular tail surrounded with feather-like appendages, and the pupa tumble about in water by means of 2 oval fins. These larvæ, and those of most flies which have 4 or 6 bristles in the proboscis, have a distinct horny head, and cast their skins to become pupa, which are generally of a brownish color; many have thorns and prickles on the body by which they work their way out of their coverings; a few cover themselves with silken webs and spin cocoons. The larvae of other flies, with a soft retractile head, living by suction, increase rapidly in size, and change their form without casting off their skins, which shorten and harden, forming a case within which the larva changes into a pupa, which comes forth a fly by forcing off one end of the case. Though this order contains the bloodthirsty mosquito, the disgusting flesh fly, and many insects depositing their eggs in the bodies of living animals, it is a most useful one, supplying food to insectivorous birds, and themselves consuming decomposing animal and vegetable substances which would otherwise infect the air. Their life in the perfect state is short, very few surviving the rigor of winter. Among the genera with many-jointed antennæ the following are the most interesting and best known: Culex (Linn.), containing the well-known gnats and mosquitoes, whose larvæ and pupa are so common in stagnant water, called wigglers and tumblers, and whose adult females pierce with their lancets and annoy by their nocturnal hum the human race from Lapland to the tropics; the best known species are the C. pipiens of Europe, and the C. Americanus of this country, which is probably distinct. The genus cecidomyia (Latr.) includes many species interesting to the agriculturist, as the Hessian fly (C. destructor, Say), the wheat fly (C. tritici, Kirby), the willow gall-fly (C. salicis, Fitch), injurious in the larva state. The genus tipula (Linn.), especially the T. oleracea (Linn.), commonly known in England by the name of Harry Long-legs, is noted for its depredations in the larva condition on the tender roots of meadow plants. In the genus simulium (Latr.) are the black fly and the midges of the northern parts of this country; the black fly (S. molestum, Harris) fills the air during the month of June in Canada and the northern states; it flies in the daytime, and is so savage that every bite draws blood, in some

skins accompanied by considerable irritation; it is black, with transparent wings, and about of an inch long. After continuing through June, it is followed by another species (S. noci cum, Harris), called "no-see-'em" by the Indians of Maine from their minuteness; they come forth toward evening, creep under any kind of garment, and produce a sharp, fiery pain without drawing blood; they are very troublesome to travellers and new settlers in July and August. Among those with few joints in the antennæ is the genus tabanus (Linn.), which contains the large horse flies, as the T. bovinus (Linn.), of a dark brown color, and an inch long, common in Europe, where there are more than 40 other species; the most common of the American species are the T. atratus (Fabr.), of a black color, with a whitish bloom on the back; the eyes are very large, of a shining black color, with 2 jet-black bands across them; it is about an inch long, with an expanse of wings of 2 inches; the orange-belted horse fly (T. cinctus, Fabr.) is smaller and less common, black, with the first 3 rings of the body orange; a smaller species is the T. lineola (Fabr.), with a whitish line along the top of the hind body. In the summer these flies are very troublesome to cattle and horses, being able to pierce through the thickest hide with their 6-armed proboscis; a strong decoction of walnut leaves applied as a wash is said to keep them off. The golden-eyed forest flies (chrysops, Meig.) are known by their brilliant spotted eyes and their banded wings; smaller than horse flies, they resemble them in their habits, frequenting woods and thickets in July and August; some are wholly black, others striped with black and yellow. The bee fly (bombylius æqualis, Fabr.) flies with great swiftness through sunny paths in the woods, hovering over flowers and sucking their honey, like humming birds; it is about of an inch long, shaped like a humble-bee, and covered with yellowish hairs; the expanse of the wings is about an inch; they are divided longitudinally into 2 equal parts by the colors, the outer half being dark brown and the inner colorless. Among the flies which prey on other insects, seizing them on the wing or on plants, is the genus midas (Latr.), of which the orange-banded species (M. filatus, Fabr.) is sometimes 14 inches long and 24 inches in expanse of wings; the general color is black; it frequents the woods in July and August, where it may be often seen flying or basking in the sun; the larva is a cylindrical maggot, growing to the length of 2 inches; the pupa measures 11 inches in length, is of a brown color, with forked tail, 8 thorns on the fore part of the body, and numerous sharp teeth on the edges of the abdominal rings; it pushes itself half out of its hole when the fly is about to come forth. The genera laphria (Fabr.) and asilus (Linn.) are also predaceous in the winged state; in the former the antennæ are blunt at the end, in the latter slender-pointed; the former resemble large humble-bees in their thick and heavy bodies and legs; in the

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larva state these asilians live in the ground, where they do much mischief to the roots of plants. The soldier flies (stratiomyda) have 2 spines on the hinder part of the thorax; the proboscis contains only 4 bristles, and ends with fleshy lips adapted for sucking vegetable juices; they are fond of wet places, and their larvæ live in stagnant pools, some thrusting their breathing tube out of the water; they undergo transformation within the hardened larval skin. The genus stratiomys (Geoff.) has a broad oval body, of a dark color, with yellow markings on each side, and the antennæ somewhat spindleshaped. The genus sargus (Fabr.) is said to have no spines on the thorax, a slender body, of a brilliant grass-green color, about an inch long, with a bristle on the end of the antennæ. These insects delight in sunny weather, being dull and inactive in cloudy days; the larvæ are found in dung and rich mould. The syrphido have also a fleshy proboscis, and live on the honey of flowers; they resemble bees, wasps, and hornets in the shape and colors of their bodies, and they sometimes lay their eggs in the nests of these insects; others drop their ova among plant lice, which the young eagerly feed upon. The larvae of the genus helophilus (Meig.) were named by Réaumur rat-tailed maggots, from the great length of their tubular tails, which serve as respiratory organs; the experiments of Réaumur show that while the insect lies concealed in mud, its respiratory tube may reach 5 inches to the surface of the water; it seems to be composed of 2 portions, which slide one into the other like the joints of a telescope; some of the larvae of this family live in rotten wood. The family conopida resemble slenderbodied wasps; the antennæ are long and 8jointed; the proboscis long, slender, and geniculate. The genus conops (Linn.) is generally of a black color, and about an inch long; more than 20 species are described, usually found on flowers in June and July, but not in large numbers; the females deposit their eggs in the larvæ and the perfect insects of the humble-bee, in whose bodies their young undergo metamorphosis. The common stable fly belongs to the genus stomoxys (Fabr.); the flesh fly to the genus sarcophaga (Meig.); the house fly and the meat fly to the genus musca (Linn.); the flower flies to the genus anthomyia (Meig.); the cheese fly to the genus piophila (Fallen.); the dung fly to the genus scatophaga (Meig.); the fruit and gall flies to the genera ortalis (Fallen.) and tephritis (Latr.); these will be described in the article FLY. The gadflies or bot flies, comprising the genera astrus (Linn.) and gasterophilus (Leach), affecting respectively the ox and the horse, will be described under GADFLY. Various winged and wingless ticks, infesting the horse, sheep, and birds, belonging to the order of diptera, but forming with the spider flies the order homaloptera of Leach and the English entomologists, will be treated in the article TICK; they include the genera hippobosca (Linn.), melophagus (Latr.), and ornithomyia (Latr.).—At the

end of this order may be mentioned the genus nycteribia (Latr.), the spider fly, a wingless insect resembling a spider; the small head seems a mere tubercle on the anterior and dorsal portion of the thorax; the eyes are like minute grains; the thorax is semicircular; the antennæ are extremely short, inserted close together, and immediately in front of the eyes. This genus nestle in the hair of bats, among which they move with great rapidity; according to Col. Montagu, when they suck the blood of bats they are obliged to place themselves on their backs on account of the dorsal position of the head. This last division of the diptera is not produced from eggs deposited in the usual manner, but the larva is hatched and developed within the body of the mother, and is not born till it arrives at the state of pupa; hence these genera have been called pupipara by Latreille; the pupa when born is nearly as large as the parent, enclosed in a cocoon, the altered skin of the larva at first soft and white, but soon grow. ing hard and brown; it is notched at one end, where the mature insect escapes. The order of diptera makes up for the small size of its members by their countless swarms.

DIPTYCHA (Gr. dis, twice, and Truέ, fold, tablet), registers used during the first Christian centuries, formed of 2 tablets of wood or ivory, upon which were inscribed the names of those most distinguished in church and state. They were thus of 2 kinds, the sacred and profane. On the former were catalogued the names of popes, bishops, martyrs, founders of religious establishments, and in general all benefactors of the clergy. The names of the living were on one side of the tablet, and of the dead on the other. It was the deacon's office to recite these names during the service. The profane diptycha belonged especially to the consular dignity, and upon their tablets were engraved the name and titles of the consul, and also animals and gladiators as symbols of the games which he was going to exhibit to the public in entering upon his duties. Every consul after his nomination had several of these diptycha, which he distributed among his principal officers, as modern princes sometimes send their portraits to privileged favorites. DIRECTORY, EXECUTIVE (Fr. directoire exécutif), the name given to the executive government of the first French republic by the constitution of Fructidor, year III. (Aug. 1795). This constitution was framed by the moderate republican party, whose influence prevailed in the convention after the fall of Robespierre and the committee of public safety, and was adopted in the primary assemblies of the people. The legislative power was vested by it in 2 assemblies, the council of 500, and the council of ancients, which numbered half as many members, aged at least 40. Both were chosen by graduated elections, and of each were renewed every year. The former had exclusively the right of proposing laws, the latter that of sanctioning them. The judicial authority was committed to elective judges. The executive directory

consisted of 5 members, and was chosen one each year by the council of ancients from a list of candidates presented by that of 500. The directory promulgated the laws and enforced their execution, appointed the ministers and other principal functionaries of the state, had the management of the military and naval forces, finances, and foreign affairs, and the right of repelling hostilities, though not of declaring war. The directors received a large salary, the palace of the Luxembourg as their residence, and a guard of 240 men. They were responsible, decided questions by a majority vote, and presided by turns 3 months each, the presiding member having the signature and the seal. During their term of office none of them could have a personal command, or absent himself for longer than 5 days from the place where the councils held their sessions, without their permission; and after they had left office they could hold no command for 2 years, nor be reelected for 5. In those days of violent struggles at home and abroad, the balance of power established by this constitution excited antagonism between the different branches of the government, and usurpations followed as a natural consequence. The convention decreed, by a law not included in the constitution, that in the first election of the members of the 2 councils should be chosen from its own body. This arbitrary act led to violent agitations in Paris, and finally to an insurrection of the royalist sections on the 13th Vendémiaire (Oct. 5, 1795), which was suppressed by Barras and Bonaparte. The convention having held its closing session on Oct. 26, the 2 councils held their first on the 28th, and on Nov. 1 elected Barras, LaréveillièreLépeaux, Rewbell, Letourneur, and Carnot, as directors, all of whom had voted for the death of Louis XVI. Their first proclamation, written on a broken table in a destitute room of the Luxembourg, promised a firm rule, and inspired confidence; and in spite of the exhausted position of the state, the terrible depreciation of the currency, the destitution of the army, and a pressing famine, trade, speculation, and even luxury soon revived. The democratic and communistic conspiracy of Babeuf was easily suppressed (May, 1796). Čarnot organized the armies, and directed their movements and victories; Moreau received the command of the army of the Rhine, Jourdan that of the Sambre and Mense; Hoche suppressed the insurrection in the Vendée, and Bonaparte conquered Italy. But the elections of the year V. (May, 1797) gave the royalists a preponderance in the councils, which was supported by the minority of the directory, while Barras, Laréveillière, and Rewbell sided with the minority in the legislative bodies. The movements of the royalists became more and more threatening, when the majority of the directors agreed to save the republic by an act of violence. This was executed with the aid of the army on the 18th Fructidor (Sept. 4, 1797). More than 50 members of the 2 councils, with Carnot and Barthélemy, who had

DIS

replaced Letourneur, and a number of other influential persons, were condemned to transportation, and a persecution of both royalists and anarchists was commenced. Merlin of Douai and François of Neufchâteau were substituted for the 2 proscribed directors, of whom Carnot escaped to Germany. Saved by the army of the interior, the republican rule was maintained by the victories and extortions of the armies abroad. The treaty of Campo Formio was concluded; Switzerland and the states of the church were overrun and revolutionized; Bonaparte was sent to Egypt to attack indirectly England, the only remaining enemy of the republic. But the extreme revolutionary party carried the elections for the year VI. (May, 1798), a part of which were annulled by another violation of the constitution. A new coalition against France was formed. The state was exhausted and avowedly bankrupt. Switzerland and Italy were lost as rapidly as won. The republicans, too, were impatient of the dictatorial rule of the directory, in which Treilhard had replaced François, and Sieyès, an enemy of the directorial constitution, was now elected (May 16, 1798) instead of Rewbell. Finally the councils, having declared themselves permanent, compelled Treilhard, Merlin, and Laréveillière to resign on the 30th Prairial (June 18, 1799). Barras saved his office by the desertion of his associates, and maintained himself with Sieyès and the 3 new directors, Gohier, Moulins, and Roger Ducos, till the 18th Brumaire (Nov. 9, 1799), when Bonaparte, suddenly returning from Egypt, by a bold coup d'état overthrew the directory and the constitution, and became master of France under the title of consul. The directory ruled France 4 years and a few days, and had altogether 13 members, of whom only Barras officiated during the whole period.

DIS, a contraction of dives, rich, the Latin name of Pluto (the giver of wealth), and hence sometimes of the lower world. He was especially worshipped among the Gauls, who believed themselves his descendants, and therefore reckoned their time by nights instead of days. DISCIPLES, CHURCH OF THE. The religious body, variously designated as "Disciples of Christ," "Christians," the "Church of Christ," &c., resulted from an effort to effect union among the Protestant denominations in western Pennsylvania. In the beginning of the present century several religious movements for this purpose occurred in different parts of the United States, independently of each other, and with out preconcert. The one which gave immediate origin and distinctive character to the body now known as "Disciples," was initiated in 1809 by Thomas Campbell, a preacher of piety and distinction among the Seceders, aided by his son Alexander, to whose ability and energy its successful progress is mainly attributed, and by whom it has been chiefly directed. The original purpose was to heal, if possible, the divisions of religious society, and to develop and establish a common basis of Christian union. It was

thought that these desirable objects could be attained by taking the Bible alone as a guide, and its express teachings as the only authoritative standard of faith and practice, allowing meanwhile entire liberty of opinion in relation to all matters not fully revealed. Upon these principles a considerable society was formed, consisting chiefly of members from Presbyterian churches, and meetings were held statedly for the promotion of the cause of union and for religious worship and instruction. After some time, the question of infant baptism, and, as connected with it, the use of sprinkling as baptism, became matters of investigation in the society, and it was finally after some months decided by a large majority that there was no Scripture warrant for either practice, and that consequently, upon their own principles, they were compelled to renounce them. Becoming then a society of immersed believers, they soon after were united with the Redstone Baptist association, stipulating, however, in writing, that " no standard of doctrine or bond of church union, other than the Holy Scriptures, should be required." By means of this union with the Baptists, the principles and views of the Disciples, ably developed and defended by Alexander Campbell in his writings and public discussions, were widely disseminated, and adopted by many. Meanwhile, the diligent study of the Scriptures, contemplated as it were de novo, and from a standpoint outside of all denominational and sectarian lines, led by degrees to the discovery and introduction of several characteristics of primitive Christianity which, as the Disciples held, had been long overlooked and neglected. Among these, a prominent one was "baptism for the remission of sins." As the apostle Peter, to whom the keys of the kingdom of heaven were committed, commanded believing penitents who asked what they should do to be "baptized in the name of Christ for the remission of sins," and in order that they "might receive the gift of the Holy Spirit" (Acts ii.), it was believed that the same answer should still be given to such inquirers, and that it was the divine plan thus to impart through the significant institution of baptism that assurance of pardon which many in modern times have been taught to seek in vague emotional impressions. This became therefore a distinguishing feature of the reformation urged by the Disciples. Another characteristic was the practice of weekly communion, after the example of the primitive church. In pressing these matters upon the acceptance of the Baptists, a spirit of opposition was at length aroused in various quarters, especially in Virginia and Kentucky, and a separation to some extent ensued, many of the Baptists remaining connected with the Disciples. Not long afterward, at the close of 1831, their numbers were still further augmented by a union between them and a numerous body which had originated in Kentucky and some other western states, under the labors of B. W. Stone and others, who, some years prior to the movement

led by Thomas and Alexander Campbell, had separated from the Presbyterian communion, and in like manner attempted to effect a union of Christians upon the Bible alone. These reformers, readily adopting baptism for remission of sins, and the ancient order of things as practised by the Disciples, became entirely assimilated with the latter. Since this period there has been a great and constantly increasing accession both from the world and from other religious denominations, and it is believed that the number of members in the United States is now about 300,000. There are many churches also established in British America, in Great Britain, and in Australia. Although the Disciples reject creeds as bonds of fellowship, and disapprove of the technical language of popular theology, holding themselves bound to speak of the "things of the Spirit" in the language of Scripture, they do not materially differ from the evangelical demoninations in their views of the great matters of Christianity. The following synopsis from the pen of Alexander Campbell is a fair expression of their sentiments on the points involved: "1. I believe that all Scripture given by inspiration of God is profitable for teaching, for conviction, for correction, for instruction in righteousness, that the man of God may be perfect and thoroughly accomplished for every good work. 2. I believe in one God, as manifested in the person of the Father, of the Son, and of the Holy Spirit-who are, therefore, one in nature, power, and volition. 3. I believe that every human being participates in all the consequences of the fall of Adam, and is born into the world frail and depraved in all his moral powers and capacities, so that without faith in Christ it is impossible for him, while in that state, to please God. 4. I believe that the Word, which from the beginning was with God, and which was God, became flesh and dwelt among us as Immanuel or 'God manifest in the flesh,' and did make an expiation of sin, 'by the sacrifice of himself,' which no being could have done that was not possessed of a superhuman, superangelic, and divine nature. 5. I believe in the justification of a sinner by faith without the deeds of law, and of a Christian, not by faith alone, but by the obedience of faith. 6. I believe in the operation of the Holy Spirit through the word, but not without it, in the conversion and sanctification of the sinner. 7. I believe in the right and duty of exercising our own judgment in the interpretation of the Holy Scriptures. 8. I believe in the divine institution of the evangelical ministry; the authority and perpetuity of the institution of baptism and the Lord's supper." ("Millennial Harbinger" for 1846, p. 385.) It is proper to remark, however, that with the Disciples the Christian faith does not consist in the belief of these or any other tenets as intellectual conceptions of religious truth, but in a simple trust or personal reliance on Christ as the Son of God and the Saviour of sinners. They hence require of candidates for baptism no other confession of faith than this,

following the example of Philip (Acts viii. 37). As to government, each church is independent, but the churches cooperate with each other in sustaining Bible societies and missionaries at home and abroad. Two classes of officers are recognized, elders or bishops and deacons, who are chosen by the members of each church, and to whom the interests of the congregation are confided.

DISCORD, in music, a combination of sounds inharmonious and disagreeable to the ear, so called in opposition to concord. Discords are employed to relieve a succession of pure concords, being as necessary in music as shade is in painting, and are introduced by certain preparatives and succeeded by concords to which they have a relation.

DISCOUNT, a sum of money deducted from a debt due at some future period in considerstion of immediate payment. In commercial transactions it is customary, when a bill is to be discounted, to pay to the holder or presenter the amount minus the simple interest_calcu lated for the time the bill has to run. Thus a person holding a bill for $100 payable in one year at 7 per cent. would receive $93, which would be considered its present value. The true discount, however, of any sum for any given time, is such a sum as will in that time amount to the interest of the sum to be discounted. Thus, in the above instance, the sum to be deducted from the bill would be, not $7, but $6 54 and a fraction, which would amount at the end of a year to $7. The true rule for computing discount would therefore be: "As the amount of $100 for the given rate and time is to the given sum or debt; so is $100 to the present worth, or so is the interest of $100 for the given time to the discount of the given sum." Elaborate tables have been calculated on this principle, but as abatement of the simple interest is generally resorted to, they are of little practical value.-Discount on merchandise, sometimes called REBATE, is a deduction of so much per cent. from the price of goods sold on credit when the buyer finds means to make his payment before the stipulated time.

DISCUS, among the ancients, the name of a circular mass of stone or metal, used for throwing, as an exercise of strength. This practice was of great antiquity among the Greeks. Homer gives an account of a trial of strength of this kind at the funeral games in honor of Patroclus. In this case the discus was a large globular mass of iron. Ordinarily it was of a flattened form, and about 10 or 12 inches in length, so that when held in the hand ready to be thrown, it would extend a little above the middle of the forearm.

DISINFECTANTS, substances used to counteract or destroy noxious odors and exhalations, or whatever may produce infection. The term is also made to embrace substances used to prevent decay of organic bodies, such as may be found treated of in the articles ANTISEPTICS and EMBALMING. In the present article disinfect