Page:The New International Encyclopædia 1st ed. v. 01.djvu/649

ANGERS. weaving, etc., are carried on to a considerable extent, and a trade in corn, wine, brandy, flax, hemp, honey, etc. There are slate quarries in the neighborhood. Angers is the birthplace of René of Anjou, the learned Ménage, the publicist J. Bodin, and the sculptor David, whose statue was unveiled in the Place de Lorraine, October 24, 1880. Pop. in 1901, 82,398. Consult A. Debidour, La Fronde angevine; la vie municipale au 17e siècle (Paris, 1877).

AN'GEVIN LINE, or DY'NASTY. The English kings from Henry II. to John, since their family, the Plantagenets, came from Anjou in France.

ANGHIERA, an-gya'ra or ANGHERA, iin-gri'ra. See.

AN'GILBERT, (c. 740-814). A friend and privy councillor of Charlemagne, and the most distinguished poet of his age. He filled the highest offices, and in 790 became Abbot of Centula (the present St. Riquier). In 800 he assisted in Rome at the coronation of the Emperor, who called him the "Homer of the age." By Bertha, the daughter of Charlemagne, he was father of two sons, Harnid, and Nithard, the historian.

ANGI'NA PECTORIS (Lat. tightening of the chest or heart), or Heart-stroke. It is characterized by intense pain and sense of con- striction, which occur in paroxysms begin- ning oer the region of the heart, or deep in the chest, and extending toward the left shoulder. The attacks are apt to appear in succession, and ultimately they kill the patient. As to the true pathological basis of angina pectoris we are still uncertain. Changes in the heart, aorta, and arteries, varying from extensive valvular disease to a mild arterio-sclerosis, have been described. These changes are, however, not constant, and are also found in cases which die with no symptoms of angina. There is usually disease of the coro- nary or heart arteries, of the nature of an arte- rio-sclerosis or thickening of the walls. This may be especially marked at the origin of the vessels, and leads to a diminution in lumen. A'^arious theories have been advanced as to the true nature of angina. It has been considered as a neuralgia of the cardiac nerves, as a cramp of the heart muscle, as due to extreme dilatation of the heart — the tense muscle pressing the nerve endings — and as a temporary anæmia of the heart muscle due to disease or spasm of the ves- sels supplying it with blood. It must be admit- ted, however, that such suggestions are purely theoretical, and that a definite pathological basis of angina is as yet undetermined. Angina pec- toris is a disease of adult life, occurring most frequently between the ages of forty and fifty. The paroxysms may be induced by any excess in diet, by exertion, as walking uphill or against a strong wind, or by mental emotions. It is there- fore advisable for those who have had an attack of angina to lead a quiet, regular life, avoid ex- cesses of all kinds, and particularly refrain from mental excitement. During an attack the physi- cian usually administers morphine, nitrite of amyl, nitroglycerin, or chloroform.

ANGIOLIERI, an'jo-lya'rj, (c. 1250-c. 1312). An Italian humorous poet of Dante's time, born at Siena, not earlier than 1250. He sang of his quarrels with his father, his misadventures in love, and the poverty under which he suffered. His verse is original in form. No fewer than three sonnets are devoted to Dante, who, it is inferred, charged him with being a parasite, for in the last of these sonnets Cecco hurls the epithet back at him with a vigor which must have severed their relations once for all. Cecco himself figures in one of the tales of the Decameron (IX. 4). He is supposed to have died about 1312. Consult Gaspary, Italian Literature, Oelsner's translation (London, 1901).

AN'GIO'MA. See.

ANGIOSPERMS, an'ji-o-spcrmz (Gk. ἀγγεῖον, angeion, vessel + σπέρμα, sperma, seed). A name applied to the greatest group of seed-plants, Spermatophytes, as distinguished from the other group, Gymnosperms, in which the "seeds are naked." The two great divisions of Angiosperms are the Monocotyledons and Dicotyledons, once called the "Endogens" and "Exogens" respectively. The Monocotyledons are characterized by the single terminal seed leaf (cotyledon) of the embryo, the scattered woody bundles of the stem, the closed venation (often called "parallel veined"), and the three-parted flowers. To the group belong such forms as the common pondweeds, grasses, palms, aroids, lilies, and orchids. The Dicotyledons are characterized by the lateral cotyledons, the organization of the woody bundles of the stem into a hollow cylinder, the open venation (often called "net-veined"), and the five- or four-parted flowers. To this group belong such forms as the common trees (poplars, oaks, elms, etc.), buttercups, roses, peas, umbellifers, heaths, mints, composites, etc. The Angiosperms are estimated to comprise over 100,000 species, and they form the most conspicuous part of the vegetation of the earth. Since the Gymnosperms comprise only about 400 living species, it is evident that the Angiosperms are the chief modern representatives of seed-plants. It is among Angiosperms also that the true flowers are developed, with elaborate relations with insects for securing pollination. The group is often called "true flowering plants," because it is characterized by the ordinary conspicuous flower.

The members of the group are of every possible variety of habit, from minute floating forms to gigantic trees. The roots, stems, and leaves are more elaborately and variously organized for work than those of any other plant groups, and the whole structure of the body is the most complex found in the plant kingdom.

It is among the Angiosperms that "stamens" and "carpels" become definite and distinctly developed. The stamen of the Angiosperm corresponds to a spore-bearing leaf of the fern-plants, but shows no resemblance to an ordinary leaf in form. The region devoted to producing the spores is called the "anther." In observing the development of an anther it is found that four sporangia usually appear, and that as these approach maturity they fuse in pairs, resulting in the appearance of two pollen-sacs, each of which has been derived from two sporangia. Occasionally in Angiosperms the four original sporangia of the stamen remain distinct.

The carpels of Angiosperms give name to the group, for these structures inclose the ovules that become seeds, the name angiosperms meaning, as has been said, "seeds in a case." In this regard they differ decidedly from any carpels which exist among the Gymnosperms, in which