ENZYME. 133 EOSTRA. transformed into enzymes, disappearing as the enzymes increase. The enzymes whose names are italicized in the above table are described in special articles in this encyclopaedia. Consult also Green, The Soluble Ferments and Fermentation (New York, 1899). E'OBA'NTJS, Helius, also called Hr.ssus (1488-1540). A German humanist. His name properly was Eoban Koch. He was born in Hesse, probably at Halgehausen. He led the wandering life of so many scholars of that period, teaching, lecturing, and writing in different places. He was favorable to the Reformation, and showed his humanistic sympathies by participating in the famous Epistolw Obscworum Virorum, and his scholarship and poetical ability in his transla- tions" of Ecelesiastes (1532) and the Psalms (Marburg, 1537), whence his epithet 'the Hessian David.' For his life, consult Krause (Gotha, 1879). E'OCENE EPOCH (from Gk.ijut, fos, dawn + raiw5s, kainos, new). A division of geologic time following the Cretaceous period and mark- ing the beginning of the Cenozoic era. At the end of the Cretaceous period great geographical changes occurred in both Europe and North America, by which the floor of the inland seas was raised partly into land and partly into shal- low waters. This elevation took place slowly and occupied a long interval of time, so that when the Eocene period opened the fauna and flora had assumed a decidedly modern aspect. Among in- vertebrates the ammonites, which were character- istic of the Mesozoic era, became extinct, while bivalves, such as the oyster, clam, and scallop, common at the present day, were very numerous. Ganoid fishes became subordinate to the teleosts, which included perch, herring, and sharks, and mammals predominated over reptiles. In rocks of this period have been found the remains of 'eohippus,' the earliest-known direct ancestor of the horse. The vegetation included dicotyls, palms, and grasses belonging to genera living at the present time. Eocene rocks in the United States are found along a belt that extends par- allel to the Atlantic coast from New Jersey to Florida, in the Mississippi Valley, in the Gulf States, and in California, Oregon, and Washing- ton. There are numerous basins also in the Rocky Mountain region of Utah, Wyoming, Col- orado, and New Mexico, which, unlike the preced- ing, were deposited in fresh water. The most im- portant of these basins are the Puerco, Wasatch, Green River, and Uintah. In the Uintah basin the deposits are 6000 to 8000 feet thick. The following division of the Eocene is recognized by American geologists: Atlantic and Gulf States: (a) Midway, (b) Lignitic, (c) Lower Claiborne, (d) Claiborne, (e) Jackson, (f) Vicksburg; WCstern States: (a) Puerco, (b) Wasatch, (c) Wind River, (d) Bridger, (e) Uintah. The rocks of the Eocene include clays, sands, lime- stones, and sandstones, while among the economic minerals are marls in the Atlantic States, phos- phate rock in Florida, and brown coal in Nevada. Consult Geikie, Text-Book of Geology (London, 1893). See Tertiary System; Geology. E'OHIP'PUS. See Hybacothebium ; and Horse. Fossil. EOLIAN HARP. See .^olian Harp. EOLIAN ROCKS. See .Eoijas Accumula- tions. EOLIANS. See ;Eolians. EOL'IPILE. Sec .Koi.ii'Ile. EON DE BEAUMONT, a'ON' de bo'mON', Charles d' (1728-1810). A French diplomatist, commonly known as the Chevalier d'Kcui. He un- born at Tonncrre, Burgundy, and in early life practiced as an advocate in Paris. His essay on the finances of France attracted much attention, and in 1755 lie was sent by Louis XV. on a diplo- matic mission to Russia, where he assumed the dress of a woman, gained the favor of the Empress Elizabeth, and negotiated an advantageous treaty. After serving with the French army in Germany in 1759 he was made minister plenipotentiary to London (1703), but was superseded shortly after the death of Louis XV. On his return to France (1777) the Government, for reasons which have never been made known, required him to assume the female dress, which he wore for the remainder of his life. This fact gave rise to doubts as to his sex, which were not settled until his death. On the outbreak of the French Revolution he offered his services to the French nation, but they were declined, and he passed the rest of his days in poverty in England. The Chevalier d'Eon was the author of many historical and political es- says which were published under the title of Loisirs du Chevalier d'Eon (1775). The Me- moires attributed to him and edited by Gaillar- det (Paris, 1836) are not genuine. Consult Tel- fer, The Strange Career of the Chevalier d'Eon de Beaumont (London, 1885). EON, or EU'DO DE STEL'LA, or EON DE L'ETOILE, a'SN' de la'twal'. A religious fanatic of noble birth, who lived in Brittany in the twelfth century, and claimed to be the final judge of mankind. He is said to have applied to him- self the pronoun eum, in the familiar liturgical formula, per eum qui venturus est iudicare virus et mortuos, "through Him who will come to judge the quick and the dead," whence his name. Eon. He opposed the hierarchy of the Church, al- though he did not hesitate to construct a new one of his own, ordaining his followers as bishops and archbishops, in complete disregard of canon law, for he was himself a layman. His enthusiastic adherents went forth to plunder and destroy churches and monasteries. In Eon himself mirac- ulous powers were believed to reside. He was publicly opposed at Nantes by the cardinal legate, Alberic, and Hugo, Archbishop of Rouen, wrote a book against him, Dogmatum Christiana' Fidri. In 1148 he was seized, along with some of his leading adherents, and brought before a synod at Rheims for trial. He was adjudged insane, and thus escaped execution, but he was imprisoned for the rest of his life, and some of his followers were burned at the stake. His sect soon died out. There is little ground for the commonly accepted opinion that Eon belonged to the Cathari. Con- sult : hi. C. Lea, History of the Inquisition of the Middle Ages, vol. i. (New York. 18SS) : Bollin- ger, Beitrage zur Sektengeschichte des Mittelal- ters, vol. i. (Munich, 1890). EOS. See Aurora. EOS'TRA. The Teutonic goddess of Spring. the name of whose festival has been transferred to the Christian Easter (q.v. ).