any of two different groups of ribbonlike aquatic plants. Vallisneria species (family Hydrocharitaceae), also called tape grass, are native to temperate and tropical waters; V. spiralis, often grown in aquariums, is a favourite food of wild ducks. (For its unusual ...
any of about 80 species of elongated marine fishes of the family Zoarcidae, found in cold waters and abundant in Arctic and Antarctic regions. Eelpouts are thick-lipped, eel-shaped fishes with the dorsal and anal fins connected around the end of ...
any of several worms of the class Nematoda (phylum Aschelminthes), so called because they resemble miniature eels. The term is most often applied to smaller members of the class Nematoda that are either free-living or parasitic in plants.
major division of Pleistocene time and deposits in Europe (the Pleistocene Epoch began about 1,600,000 years ago and ended about 10,000 years ago). The Eemian Interglacial followed the Saale Glacial Stage and preceded the Weichsel Glacial Stage; the Eemian is ...
marine transgression during the Eemian Interglacial Stage of the Pleistocene Epoch (the Pleistocene began about 2,500,000 years ago and ended about 10,000 years ago). The Eemian Sea flooded much of northern Europe and converted Scandinavia into a virtual island. The ...
most important island of Vanuatu, in the southwestern Pacific Ocean. Volcanic in origin, it occupies an area of 353 sq mi (915 sq km), and its highest peak is Mt. Macdonald, 2,123 ft (647 m). Its terrain is rugged and ...
number that represents the total number of electrons surrounding the nucleus of a metal atom in a metal complex. It is composed of the metal atom's electrons and the bonding electrons from the surrounding electron-donating atoms and molecules. Thus the ...
in genetics, the size of a breeding population, a factor that is determined by the number of parents, the average number of children per family, and the extent to which family size varies from the average. The determination of the ...
Dutch essayist and journalist whose straightforward didactic pieces, modelled on foreign examples, had a wholesome influence on the contemporary Dutch fashion of rococo writing. His other occupations included private tutor, secretary at the Netherlands embassy in London (1715 and 1727), ...
earthen mound in the form of an animal or bird found throughout the north-central United States. The effigy mounds are sometimes mistakenly classified with the numerous mounds that dot the area east of the Mississippi River, believed to be the ...
area of 4 square miles (10 square km) containing numerous ancient Native American burial and ceremonial mounds in northeastern Iowa, U.S., on the Mississippi River, a few miles north of McGregor. Established in 1949 and located on bluffs overlooking the ...
city, seat (1860) of Effingham county, east-central Illinois, U.S. It lies near the Little Wabash River, about 65 miles (105 km) southeast of Decatur. Settled about 1814 by farmers, the community grew slowly as pioneers moved westward along the Cumberland ...
spontaneous loss of water by a hydrated salt, which occurs when the aqueous tension of the hydrate is greater than the partial pressure of the water vapour in the air. For example, because the vapour pressures of washing soda (Na2CO3·10H2O) ...
town, Ondo state, southwestern Nigeria, in the Yoruba Hills, at the intersection of roads from Ilesha, Ondo, and Ado-Ekiti. It was probably founded in the late 19th century, when both the Ilesha and Effon belonged to the Ekiti-Parapo, a Yoruba ...
people inhabiting the lower Cross River in Cross River state, Nigeria; their dialect of Efik-Ibibio (in the Benue-Congo branch of Niger-Congo languages) has become the literary language of all educated Efik-Ibibio speakers. The Efik, an offshoot of the Ibibio, migrated ...
small mountainous group of islets belonging to Italy, in the Mediterranean just off the western coast of Sicily, with a total area of 15 square miles (39 square km). The principal islands are Favignana, the largest (7 square miles), Levanzo, ...
Portuguese neurologist and statesman who was the founder of modern psychosurgery. With Walter Hess he was awarded the 1949 Nobel Prize for Physiology or Medicine for the development of prefrontal leucotomy (lobotomy) as a radical therapy for certain psychoses, or ...
also spelled Ecgberht, or Ecgbryht king of the West Saxons from 802 to 839, who formed around Wessex a kingdom so powerful that it eventually achieved the political unification of England (mid-10th century).
town, seat of Heves megye (county), northern Hungary. It lies in the valley of the Eger River, which is a tributary of the Tisza, between the Matra and the Bukk mountains. Eger is an old Magyar tribal city with a ...
in Roman religion, a water spirit worshiped in connection with Diana at Aricia and also with the Camenae in their grove outside the Porta Capena at Rome. Like Diana, she was a protectress of pregnant women and, like the Camenae, ...
in biology, the female sex cell, or gamete. In botany the egg is sometimes called a macrogamete. In zoology the Latin term for egg, ovum, is frequently used to refer to the single cell, while the word egg may be ...
tooth or toothlike structure used by the young of many egg-laying species to break the shell of the egg and so escape from it at hatching. Some lizards and snakes develop a true tooth that projects outside the row of ...
any of the five species of the genus Dasypeltis of sub-Saharan Africa and Elachistodon westermanni of northeastern India. These snakes comprise the subfamily Dasypeltinae, family Colubridae. They eat only eggs. The mouth is enormously distensible and the teeth greatly reduced, ...
inscribed stone that bears 200 runic characters. It is the longest known text in the old-style futhark (runic alphabet) and was discovered inside a tomb in western Norway in 1917. The runes are arranged in three unequal lines, separated by ...
(Solanum melongena), tender perennial plant of the nightshade family (Solanaceae), closely related to the potato. Eggplant requires a warm climate and is grown extensively in eastern and southern Asia and in the United States. It is native to southern and ...
Chinese porcelain characterized by an excessively thin body under the glaze. It often had decoration engraved on it before firing that, like a watermark in paper, was visible only when held to the light; such decoration is called
one of the greatest of Icelandic skaldic poets, whose adventurous life and verses are preserved in Egils saga (c. 1220; translated in The Sagas of Icelanders), attributed to Snorri Sturluson. The saga portrays Egill as having a ...
leader in the early opposition to the policies of Philip II of Spain in the Netherlands. Although Egmond did not favour the overthrow of Spanish sovereignty, he became one of the first and most illustrious victims of the Duke of ...
mountain, west central North Island, New Zealand, on the Taranaki Peninsula. Named after the British earl of Egmont, the symmetrical volcanic cone rises from sea level to 8,260 ft (2,518 m) and has a subsidiary cone, 6,438-ft Fanthams Peak, 1 ...
in psychoanalytic theory, that portion of the human personality which is experienced as the "self" or "I" and is in contact with the external world through perception. It is said to be the part that remembers, evaluates, plans, and in ...
(from Latin ego, "I"), in philosophy, an ethical theory holding that the good is based on the pursuit of self-interest. The word is sometimes misused for egotism, the overstressing of one's own worth.
any member of several species of herons (family Ardeidae, order Ciconiiformes), especially members of the genus Egretta. Most egrets have white plumage and develop long ornamental nuptial plumes for the breeding season. Their habits are generally like those of other ...
country located in the northeastern corner of Africa. It has a total area of about 385,230 square miles (997,740 square kilometres). Its land frontiers border Libya in the west, The Sudan in the south, and Israel in the northeast. (Israeli ...
civilization in northern Africa dating from the 3rd millennium BC. Its many achievements, preserved in its art and monuments, hold a fascination that continues to grow as archaeological finds expose its secrets. This article deals with Egypt from its prehistory ...
dating system established several thousand years before the Christian era, the first calendar known to use a year of 365 days, approximately equal to the solar year, or year of the seasons. Until the creation of the Julian calendar, about ...
extinct language of the Nile valley that constitutes a branch of the Afro-Asiatic (formerly Hamito-Semitic) language family, along with the Semitic, Cushitic, Chadic, and Berber language groups. On the basis of texts in the language, scholars generally divide the history ...
the law that originated with the unification of Upper and Lower Egypt under King Menes (c. 2925 BC) and grew and developed until the Roman occupation of Egypt (30 BC). The history of Egyptian law is longer than that of ...
museum of Egyptian antiquities in Cairo, founded in the 19th century by the French Egyptologist Auguste Mariette and housing the world's most valuable collection of its kind. The museum was founded in 1858 at Bulaq, moved to Giza, and moved ...
