1 Japanese. Hoyei Period, 1704-1711. Costume for Uo Dance

2 Chinese. Silk, crimson and gold. (In Metropolitan Museum, New York)

broiderers. Embroidery was also one of the most important subjects of instruction, ranking in dignity with painting and sculpture. Superb articles were worked on linen grounds with worsteds, silk and gold threads. Sometimes the entire material was covered with embroidery in the style of the miniature paintings in the illuminated manuscripts of the time; and it is noticeable that the great period of church embroidery, from the 12th to the 14th century, is also the great period of the illuminated manuscripts. In these "paintings with the needle," as contemporary writers call them, the English were the most celebrated. Their special work was known as Opus anglicum. It became so famous that great lords had to have specimens in their collections and many churches throughout Europe received gifts of this artistic production. The Syon Cope, now in the South Kensington Museum, is the most celebrated specimen in existence.

Embroidery was lavished not only on copes, chasubles, dalmatics, mitres, gloves and shoes for church ceremonials in the Middle Ages, but was also used to decorate the costumes of men and women and for draperies and household decoration. Beds were magnificent with embroidered draperies and counterpanes. Nor was it sufficient to embroider one set of bed and window hangings, but several sumptuous "sets of hangings" were produced to suit the changing seasons and various occasions. Hangings for tents were also marvelously embroidered and so were the armorial bearings of the knight on his surcoat and on his banners. Much of this work was done in the convents and monasteries and by the groups of embroiderers supported in wealthy homes and much of it was done by the accomplished and noble ladies. We know this from allusions in contemporary literature and in the detailed and descriptive entries in inventories and wills.

In the 16th century embroidery was no less used. It submitted, however, to Renaissance influence. Superb work was produced in Spain, Italy, France and England. Beautiful specimens exist in private and public collections and in the treasuries of cathedral and abbey churches; and, moreover, we have the paintings of the old Italian, Flemish and Spanish masters to show what gorgeous embroideries people wore. Household articles received much work from the embroiderer and also such small articles as purses, bags, handkerchiefs, gloves and covers for books. Sets of hangings for windows and beds were embroidered and "Turkey work" and petit-point chair-seats and cushions were made. Queen Mary and Queen Anne, like Queen Elizabeth and their Stuart ancestor, Mary Queen of Scots, were expert embroiderers. They followed in their designs the general taste of the day led by the artists of Louis XIV and inspired by the growing Eastern influence. Still employed to adorn costume, the art of embroidery grew ever more and more delicate; and in the days of Louis XV, when there was a rage for Chinese decoration, the handsome coats of courtiers and men of fashion were often sent to China to be embroidered according to order with European patterns. Floss and spun silks were now made up into various new threads, such as the fluffy velvet chenille, or caterpillar cord. Delicate gold and silver

threads were also produced; and with these pretty materials beads and spangles were often mingled to make the fantastic and graceful designs even lovelier by their added brightness and sparkle.

Embroidery was still exquisite in the days of Louis XVI and in the time of Napoleon. Josephine favored delicately embroidered and filmy muslins, which shared their vogue with Cashmere shawls. French, English and American fingers were soon able to produce lovely flowered and figured muslins and to decorate tulles and nets with "tambour" until machinery was invented to make their beautiful work unnecessary.

Within the last 30 or 40 years there has been a revival of artistic needlework-a movement in which Walter Crane and William Morris took the lead. Many art schools have been formed in the United States similar to that of the South Kensington Museum in London in which the stitches and styles of ancient and decorative embroidery are taught.

Bibliography.- Christie, Mrs. Archibald H., 'Embroidery) (London 1899); Day, Louis F., 'Art in Needlework: a Book about Embroidery (ib. 1900); Dreger, 'Weberei und Stickerei) (Vienna 1904); Drew, Joan H., 'Embroidery and Design; a Handbook of Patterns (London 1915); Higgin, L., and Alford, Lady Marian, 'Handbook of Embroidery' (ib. 1880); Jourdain, M., English Secular Embroidery (ib. 1910); Kendrick, A. F., 'English Embroidery (ib. 1905); Migeon, 'Les arts du tissa (Paris 1909); Townsend, W. P. Paulson, Embroidery (London 1907).

ESTHER SINGLETON.

EMBRUM, ŏn-brun (ancient Eburodunum Caturigum), France, town in the department of Hautes-Alpes, on a rocky eminence in the centre of a large plain watered by the Durance, 20 miles east from Gap. It is an ancient place, surrounded by walls and ditches, and of very picturesque appearance. The principal buildings are a cathedral and the archiepiscopal palace. It was pillaged successively by Vandals, Huns and Saxons, and its inhabitants almost exterminated by the Moors in 966. It is still a bishop's, and was once an archbishop's see. The manufactures consist of broadcloth, hats, yarns and farm tools. Pop. 3,812.

EMBRYO. See EMBRYOLOGY.

EMBRYOLOGY, that branch of biological science which is concerned with the development of the organism from the egg. The term is applied to the development of plants as well as animal organisms, but in the present article only the latter will be considered. Though every species of metazoan or multicellular animal produces eggs, not every individual arises directly from the egg. Indeed, in some groups asexual reproduction is commoner than sexual. It may occur by fission, or division of the organism into two or several individuals, as in certain flat-worms and annelids, or by gemmation, where new individuals bud or sprout out from the older ones, and either separate completely, or remain attached, forming colonies as in hydroids and bryozoans. However, strictly speaking, embryology applies only to the development of the organism from the zygote or fertilized egg-cell, or in some cases from eggs which develop by partheno

genesis,i.e., without fertilization by a male gamete. Historical. Before the invention of the miscroscope observations on development were of the most superficial sort and the genesis of the organism from the egg was chiefly a problem for the philosopher. The relation of the embryo to the two parents was not in any sense comprehended and as late as the middle of the 17th century spontaneous generation was believed to occur in some animals, even by so great a physiologist as William Harvey. During the 17th and 18th centuries the theory of "evolution," later known as preformation, of which Bonnet, Leibnitz and Haller were among the greatest exponents, was the dominant view. Evolution in this sense denotes mere unfolding, like the flower from the bud, and has no relation to evolution in the sense of a theory of descent with modification. In brief, preformation is the doctrine that all the structures of the adult body are present in miniature in the germ and that development consists merely in their unfolding and growth. According to this theory nothing arises anew; as a corollary, known as the "emboitement" or box-within-boxtheory, the germ must contain in diminishing series the germs of all succeeding generations. Naturally, most of the preformationists believed the germ to be contained in the egg, but after the discovery of the spermatozoa by Hamm in 1677, a new school arose known as the spermists or animalculists, who adopted the view that these minute motile bodies, so obviously living, contained the germs, the egg serving merely as a nutrient medium in which the minute but fully formed offspring of male origin was enabled to grow. Some of the spermists even published figures showing a miniature human body, the homunculus, enclosed in the spermatozoön.

An important advance was made in 1759 by C. F. Wolff, who demonstrated, from observations on the developing hen's egg, that bodily parts are not performed but actually arise anew in an orderly sequence, a theory which had been advocated though not proved by Harvey a century earlier and even vaguely stated by Aristotle. This conception, which is termed epigenesis, shortly supplanted the purely speculative preformation theory, but what regulated this epigenetic differentiation remained a problem and still remains the great problem of embryology, notwithstanding a vast amount of observation and experimental research. During the 19th century great progress was made in morphological or descriptive embryology and if space permitted many important discoveries might be enumerated. The greatest of the early investigators in this field is generally admitted to be Karl Ernst von Baer (1792-1876), sometimes called "the father of embryology," who, working mainly on the chick, was the first to give an orderly account of the chief phenomena of development, including cleavage of the egg, formation of germ-layers and the differentiation of organs. Von Baer also laid the foundations of comparative embryology.

The cell theory, formulated by Schleiden and Schwann in 1838, which has so completely revolutionized biological thought, led only gradually to the recognition of the unicellular character of the gametes, egg and spermatozoön, and despite the much earlier germ

theory of the spermists it was not until nearly the middle of the 19th century that the spermatozoa were generally recognized as the agents of fertilization; indeed by many naturalists they were regarded as parasitic micro-organisms, accidentally present in the fertilizing fluid. In 1843 Martin Barry witnessed the penetration of the rabbit's egg by the spermatozoön, but strange to say the unicellular character of the two gametes, a fact of fundamental importance, was not clearly demonstrated until after 1860. As a consequence of the rapid development of comparative embryology during the middle and latter part of the 19th century, together with the newly awakened interest in organic evolution, came the recognition of embryology as one of the greatest sources of evidence of phylogenetic relationship, and it is not surprising that a generalization known as the "recapitulation theory," namely, that the individual in its development repeats in brief its racial history, should have been developed. Though this theory has frequently been forced farther than the facts warrant, it is unquestionably true that embryology has yielded highly important data as to the relationships of classes and smaller groups within the same phylum, thus confirming in many instances evolutionary evidence from comparative anatomy and palæontology. The latter part of the 19th century and the earlier years of the 20th witnessed the development of a school of experimental embryology, concerned with the physiology and the philosophy of development, with the old problem of what makes the egg develop and what factors regulate the progressive differentiation of the embryo. In this field of morphogenesis some of the leaders have been Roux, Herbst and Driesch in Europe, and Loeb, Morgan and Lillie in America. Experimental studies have shown that while organs are not preformed in the egg, still in many cases the egg substance is differentiated into formative zones at, or even before, fertilization, that it exhibits in greater or less degree "germinal prelocalization" of material for future organs, but not the organs themselves. This predeterminism in the egg has been termed "promorphology." In eggs of some animals this is so definite that removal of a portion of the egg will result in the building up of an incomplete embryo, while in other cases a fragment of an egg, or each of the first four or eight cells of the segmenting egg if artificially separated, will give rise to an entire dwarf embryo; hence it is not possible to make categorical statements regarding promorphology in general. It is, however, a very different conception from the old preformation theory and does not imply a negation of epigenesis. In some types the normal promorphology, even though very early established, is readily alterable, in other cases it is not. As to the general factors of differentiation, the majority of physiologists undoubtedly incline toward a purely mechanistic explanation, or interpretation in terms of chemical and physical laws, but vitalism also has able exponents, notably Hans Driesch. A discovery of peculiar interest in connection with promorphology is the phenomenon known as "polyembryony," or the development of two or more embryos from a single zygote. The most familiar example is the production of the so-called "identical twins"