Rome in 1074, and a decretal was issued that every layman who should receive the communion from the hands of a married priest should be excommunicated, and that every priest who married or lived in concubinage, should be deposed. The decree met with the most violent opposition in all countries; but Gregory succeeded in carrying it out with the greatest rigour; and though individual instances of married priests were still to be found in the 12th and 13th centuries, the C. of the Roman Catholic clergy was established, and has since continued both in theory and practice.

The violence thus done to human nature did not fail to avenge itself in those rude times. The licentiousness and corruption of the priests and monks became in many cases boundless, and it was in vain that strict individuals, as well as councils, strove against it. The immorality and debasement of the clergy became a reproach and by-word in the mouth of the people, and gave a powerful impulse to the religious movement that began in the 16th century. The leading Reformers declared against the C. of the clergy as unfounded in Scripture, and contrary to the natural ordinance of God, and Luther set the example of marrying. This was not without effect on the Roman Catholic clergy, and the question of the abolition of C. was raised at the council of Trent (1563). But the majority of voices decided that God would not withhold the gift of chastity from those that rightly prayed for it, and the rule of C. was thus finally and for ever imposed on the ministers of the Roman Catholic Church. Those who have only received the lower kinds of consecration may marry on resigning their office. For all grades above a subdeacon, a papal dispensation is necessary. A priest that marries incurs excommunication, and is incapable of any spiritual function. If a married man wishes to become a priest, he receives consecration only on condition that he separate from his wife, and that she of her free will consent to the separation and enter a religious order, or take the vow of chastity. The priests of the united Græco-Catholic congregations in Rome have received permission from the popes to continue in marriage, if entered into before consecration, but on condition of always living apart from their wives three days before they celebrate mass.

Notwithstanding these decisions, the contest against clerical C. has again and again been resumed, in recent times, both within and without the Roman Catholic Church. In fact, all attempts at innovation within the bosom of Catholicism, connect themselves with the attack on C., the abolition of which would deeply affect the constitution and position of that church. So far back as 1817, the Catholic Faculty of Tübingen expressed the opinion that compulsory C. was one of the chief causes of the want of Catholic ministers. In 1826, the Catholic clergy of Silesia put in petitions to the bishop for the abolition of C.; and unions were afterwards formed in Baden, Würtemberg, Bavaria, Silesia, and Rhenish Prussia, which, along with alterations in the doctrines and ritual of the Romish Church, combined attacks on the prohibition of marriage to the clergy. A work was also published, entitled The Introduction of Compulsory Celibacy among the Christian Priesthood, and its Consequences (Altenb. 1828, new ed. 1845), which excited great attention. At last the abolition of the law came to be discussed in the legislatures of Baden, Saxony, and other countries. The church claimed this subject as belonging exclusively to her jurisdiction, and not to that of the state; and in Würtemberg the clergy induced the government to suppress the anti-celibacy society; but this only made their opponents in the press the more zealous. In

France, also, the question, about 1829, was eagerly discussed. And in Spain, the Academy of Ecclesiastical Science took the subject into consideration in a meeting held in 1842; while the Portuguese Chambers had previously, in 1835, discussed it, though without result. The same took place in Brazil, about 1827.

During the commotions of 1848, the subject was again brought into prominence in Germany. The German Catholics (q. v.) had already abolished C.; and a general measure was called for in the Frankfort parliament, in the Prussian Assembly, and in the press. In Austria, also, voices were raised against it; but here the state took the side of the pope, who, in a bull of 1847, had added fresh stringency to the rule of C., and condemned its infringement. See BACHELOR.

CELL (Lat. cella, from celo, to conceal). The Latin word had nearly all the significations which we attach to the English one, and a good many besides which we have not borrowed. For example, the whole space within the walls of an ancient temple was called the cella. But the interior was frequently divided into several cellæ, in which case each C. took the name of the deity whose statue it contained, and was called the C. of Jupiter, Juno, Minerva, and the like. In these cases, the word approached to its general meaning, which, with the Romans as with us, was that of a store-room, or small apartment where objects of any kind were stowed away. In modern architecture, the term Vaulting C. signifies the hollow space between the principal ribs of a vaulted roof.

CE'LLÉ, or ZELL, a town of Hanover, on the left bank of the Aller, which at this point becomes navigable, 23 miles north-east of the city of Hanover. It is situated in the midst of a sandy plain, well built, and has a palace with a garden, in which Matilda, sister of George III., is buried. The inhabitants, about 10,000, are very industrious. The chief manufactures are linen, hosiery, tobacco, wafers, soap, &c. An active commerce is also carried on by the Aller, and by railway.

CELLI'NI, BENVENUTO, a celebrated Italian gold-worker, sculptor, founder, and medailleur, remarkable not only for his skill as an artist, but also for his checkered life, was born at Florence in the year 1500, and first displayed skill as a chaser and gold-worker. His autobiography is a remarkably curious and interesting work, presenting us with a complete picture of the author's life and character; his activity, his extraordinary weaknesses, the inpetuosity of his passions, the perilous circumstances in which his quarrelsome disposition placed him (for C. thought nothing of committing manslaughter in a moment of rage), and the ludicrous vanity and credulity which are never absent from him. The book is also of great value in a historico-social point of view, but does not impress us favourably in regard either to the personal or social morals of the time.

At an early period, having been banished from Florence in consequence of an 'affray,' C. went to Rome, where he was employed by many distinguished patrons of art, but afterwards was allowed to return to Florence. Another affray' compelled him to flee to Rome a second time, where he secured the favour of Clement VII. C., by his own account, was as great in arms as in art; he declares that it was himself who killed the Constable Bourbon and the Prince of Orange at the siege of Rome. His reckless conduct for some years compelled his constant shifting between Rome and Florence, Mantua, and Naples. In 1537 he went to the court of France, where he was very honourably received. Illness, however, induced him to return yet once more to

Rome, where he had the misfortune to be imprisoned on a charge of plundering the treasures in the castle of St Angelo during the siege of Rome. At length he was liberated, through the intercession of the Cardinal of Ferrara, for whom he executed, out of gratitude, a fine cup, and various other works. He now accompanied his deliverer to France, and entered the service of Francis I.; but having incurred the displeasure of the ruling favourite, Madame d'Estampes, he returned to Florence-not, however, until, as usual, he had settled some matters with his 'sword'-where, under the patronage of Cosmo de' Medici, he executed several fine works in metal and marble among them, the celebrated bronze group of Perseus with the Head of Medusa,' which now decorates the market-place in Florence. Among other preserved works of C., the splendid shield in Windsor Castle may be noticed. In his 58th year, he commenced writing his autobiography, and died in 1570 or 1572.

CELLS, in Physiology.-I. ANIMAL CELLS.-On examining, under a high magnifying power, any of the constituents of the animal body, we perceive that the smallest parts which appear to the naked eye as fibres, tubes, &c., are not ultimate elements in respect to form (morphotic elements), but that they contain and are built up of certain extremely minute particles, which differ in different organs, but always have a similar appearance in the same organs. By far the most important of these microscopic forms, which are known by histologists as 'simple elementary parts,' are the C., which not only form the starting-point of every animal and vegetable organism (the ovum in either kingdom of nature being simply a cell), but also either as C., or after having undergone certain modifications which will be presently describedmake up the tissues and organs of the perfect animal. Indeed, some of the lowest plants (red snow, gory dew), and of the simplest forms of animal life (GREGORINÆ, &c., q. v.), appear to consist of a single cell (see fig. 1).

While in plants the elementary parts generally unite directly with one another, in animals they are usually combined by an interstitial substance, which may be either solid or fluid, and is always derived from the blood or general nutrient fluid. If this interstitial substance take a part in the formation of the C., it is called a cytoblastema or a blastema, from kutos, a cell or vesicle, and blastema, germsubstance; if it has nothing to do with their maintenance, it is called the matrix. The cytoblastema is usually fluid, as in the blood, chyle, &c.; while the matrix is solid, as in cartilage, bone, &c.

In every cell, we can distinguish, if we use sufficiently high magnifying powers, a membranous envelope, known as the cell-wall or membrane, and certain contents. The latter are fluid or gelatinous, and besides containing particles or granules, usually exhibit a peculiar rounded body, the nucleus; which, again, contains in its interior a fluid and a still smaller corpuscle, the nucleolus.

forms may be mentioned: a, the polygonal, as in pavement epithelium, or the pigment of the eye; b, the conical or pyramidal, as in ciliated epithelium; c, the cylindrical, as in cylinder epithelium; d, the fusiform, or spindle-shaped, as in contractile fibre-C.; e, the squamous, as epidermic scales; and f, the caudate, polar, or stellate, as the C. in the gray nervous tissue (see fig. 2).

With regard to size, the largest animal C.-excepting the unicellular organisms-are the yolk-C. of the ova of birds and amphibia, while the blood-C. of certain animals may be taken as representing the smallest cells. Average C. range from 0·005 to 0-01 of a line in diameter.

The cell-membrane is usually transparent and colourless, mostly smooth, and so thin as to exhibit only a single contour, rarely of any measurable thickness. No traces of structure can be detected in it. The granular appearance which the membrane occasionally presents, is due to projections depending on granules lying on the inside; and it vanishes on the addition of water, which causes the cell to be distended by endosmosis. See OSMOTIC ACTION.

C. which contain only fluid are rare (fat-C., blood-C.); generally, besides fluid, they contain elementary granules and vesicles, and sometimes crystals. As a general rule, the number of these morphotic elements increases with the age of the cell; sometimes, however, this is not apparent, in consequence of their being grouped in a single mass around the nucleus.

The nucleus is usually spherical or lenticular, transparent, and either colourless or yellowish, and ranges from 0.002 to 0004 of a line in diameter. All nuclei are vesicles, as was originally maintained, in 1841, by Schwann (Microscopical Researches into the Accordance in the Structure and Growth of Animals and Plants, Sydenham Society's translation, 1847, p. 173), who must be regarded as the

while others, again, are conjoined by an intercellular substance of some kind.

2. Metamorphosed Cells. To these belong-The horny scales: flattened, polygonal, or fusiform; their membrane being fused into one mass with their contents. They occur in the epidermis, the laminated pavement epithelium, and the hair and nails. The contractile fibre-C.: fusiform, slightly flattened, considerably elongated C., whose membrane, with its soft, solid contents, is changed into a contractile substance. They occur in the smooth or involuntary muscles. The tubules of the crystalline lens of the eye: very elongated C., with viscid, albuminous contents. The prisms of the enamel of the teeth: greatly elongated, prismatic, and strongly calcified cells. The bone-C.: thickened C. (with canaliculi, or minute branching canals) which have coalesced with the matrix of the bones. The transversely striated muscular C.: large polygonal C. whose contents have become metamorphosed into a transversely striated or striped tissue, such as is found in voluntary muscular fibre. From these C. are formed all the different fibres, net-works, membranes, tubes, &c.; in short, all the higher elementary parts of which the animal body is composed.

For further information on C. and cell-development, the reader is referred, in addition to the works quoted in this article, to Leydig, Lehrbuch der Histologie des Menschen und der Thiere, 1857; and to Frey, Histologie und Histochemie des Menschen, 1859; while he will find full details on morbid cell-development (the development and growth of C. in tubercle, cancer, and other morbid deposits) in Vogel's Pathological Anatomy of the Human Body, translated by Day, 1847; and in Wedl's Pathological Histology, translated (for the Sydenham Society) by Busk, 1855.

II. VEGETABLE CELLS.-In the vegetable, as in the animal kingdom, the primary form of the cell is that of a sphere. There are, however, interfering influences, which usually alter or modify the primary form, of which the most important are, (1.) Special directions assumed in the development, in obedience to a law regulating the structure of the tissue in which the cell occurs; and (2.) Obstructions to the expansion of the cell in certain directions from the pressure of surrounding cells.

The most common forms referrible to the law of development are, (1.) The spherical or fundamental form; (2.) The cylindrical, in which there is a tendency to elongation in the direction of a vertical axis; and (3.) The tubular, in which there is an excess of development in the direction of the two

transverse axes.

The secondary modifications of these forms are numerous. Thus, in lax tissues, the spherical form may become an irregular spheroid, running out into lobed, and even stellate forms, as may be seen in the pith of rushes and the stems of various aquatic plants. Again, in seeds, the hard part of fruits, &c., the mutual pressure of the C. converts the spherical into polyhedral forms, of which the dodecahedron giving a hexagonal section, and arising from equal pressure in all directions-is the most common, although cubic and many other forms occasionally

Both the cell-wall and the contents differ from the corresponding parts in animal cells. In all young C. the wall is membranous, freely permeable by water, elastic, and flexible. In many cases it retains these properties, whilst in others it becomes much modified, as the cell grows older. It consists mainly of CELLULOSE (q. v.). As the vital and chemical phenomena exhibited by plants depend primarily upon operations in the interior of the cell, the careful study of the cell contents is of the highest importance. Of these contents, the most important are the primordial utricle, with the protoplasm, the nucleus, chlorophyll corpuscles, and starch granules. The primordial utricle is a layer of substance of mucilaginous consistence (coloured yellow by iodine), lining the entire wall of the young cell, but often disappearing at a comparatively early period. The protoplasm is a tough mucilaginous and frequently granular fluid, which fills up the space in the interior of the cell not occupied by the nucleus. The nucleus or cytoblast is a globular or lenticular body, identical in its character with the substance of the primordial utricle, and occurring in the protoplasm of most young cells. Little is known with certainty regarding the chlorophyll corpuscles, except that, under the influence of solar light, green colouring matter is developed from them. Of the starch granules, which are very commonly found in the cell contents, we need not speak, as they are sufficiently described in the article STARCH.

In addition to the above organised structures, we must mention as frequent constituents of the cellcontents, fluid colouring matters, essential and fixed oils, resins, sugar, dextrine, gum, alkaloids, and mineral or organic salts, which are not unfrequently found in a crystalline form, when they are termed raphides.

There are two modes of cell-development in the vegetable kingdom-viz. (1.) Cell-division, where two or more new cells fill the cavity of the parent cell, and adhere to its membranes, appearing to divide it into compartments; and (2.) Free cell-formation—not to be confounded with a process of the same name which is supposed to occur in the animal kingdom-in which the whole or part of the cell-contents become detached from the cell-wall and resolved into new loose C., which ultimately escape from the parent cell. The former mode universally occurs in the formation of the C. by which growth is effected; the latter occurs only in the production of C. connected with reproduction. For further information, we must refer the reader to Von Mohl's Principles of the Anatomy and Physiology of the Vegetable Cell, translated by Henfrey, London, 1852.

occur.

entire organs, it at the same time performs a similar function in regard to the minute parts of which each organ is made up. Thus, for instance, in muscular tissue, it enters between the fibres of the muscle, uniting them into bundles; and similarly, it enters