limestone stratum belonging to the basal portion of the Carboniferous system underlies a large part of the interior plain. The upper Carboniferous rock has been destroyed by erosion except in a few places. Silurian rock underlies nearly all of the northern part, but the Cretaceous, Triassic, and Permian formations exist and appear at the surface in several places. Some of the cliffs of the north are of basaltic formation. The Giant's Causeway (q.v.) on the north coast of Antrim is basaltic. Its 40,000 or more, perfectly formed polygonal columns constitute remarkable specimens of this formation. Crystalline rocks form the axis of the mountains of the province of Connaught, and the highlands of Leinster. Old red sand stone and carbonifercius limestone are found in the southwestern counties. Marble exists in large quantities in the county of Kilkenny and in parts of the adjacent counties coal of an anthracite variety is found, but not in large quantities; iron-ore exists in nearly every county. Copper of an excellent quality is in the western mountains, also gold and silver in small -quantities.
The erosion of the limestone rock which has been going on for ages has contrib uted largely to the fertility of the soil of Ire land. The igneous rocks, the red marls, and other mineral formations, have added to the richness of the soil, and all have been distrib uted, by the gradual removal of the ice-covering, over a large area of the plain. After deducting the area, about one-fifth of the whole, which is covered by bog, mountain, and moorland, there is left a vast extent of arable surface covered with 'a deep friable loam of remarkable rich ness. In addition to the decomposed trap and the calcareous matter derived from the lime stone, there is a large amount of vegetable mold which forms one of the most important ingredients of the soil. The bogs, useless for tillage, furnish peat for fuel, 'the Bog of Allen is the largest one in Ireland.
The warm moist winds from the Atlantic blowing over Ireland affect its climate more than any other cause except its latitude. The mean temperature is from 20° to 30° F. higher than other places in the same latitude on the eastern coast of America or the interior of Europe, and a few degrees higher than places in the same latitude on the west coast of Amer ica. The summer temperature is modified by the surrounding waters, being lower by a few degrees than inland places of the same latitude. The moisture brought by the winds from the ocean causes a heavy annual rainfall, and much fog, mist and general dampness. The low mountains serve to some extent as, condensing agents, so that the greatest rainfall is near the coast.
The climate and soil are very favorable for vegetation. Its mild temperature and humid atmosphere enable several delicate plants, which usually in the same latitude can be cultivated only in sheltered gardens, to flour ish here with vigor in the open air; and fre quently forest trees continue to retain their foliage after similar trees have lost their leaves in the warmest parts of England. The condi
tions would naturally indicate forests, and it seems that in early times, large tracts of mag nificent timber were spread over its surface; but waste and mismanagement have prevailed, trees have almost disappeared except from the parks of the wealthy land-owners, and what ought to be among the best is about the worst wooded country in the middle latitudes of Europe. More attention is now being given to the subject of forestry; in 1901 there were 309,741 acres in Ireland under forest, a por tion of which was a new growth. During that year, 1,740 acres were planted with trees, mostly fir, spruce, and larch. In 1917 the acreage was only 292,684, a decrease of 17,057 acres. Grass grows luxuriantly in nearly all parts of the island.
The fauna of Ireland consists now of birds and small rodents. Animals once found here and mentioned in the ancient liter ature, as the deer, bear, wildcat, wolf, beaver, cattle peculiar to the island, and certain birds (including the garefowl), have all disappeared. There are no snakes nor toads in Ireland. Fish are plentiful in the streams and on the coasts.
The salmbn fisheries are very valuable, and are increasing in value every year. With ah increased supply of 'fish, high prices are maintained owing to the improved means of communication from remote districts with the best markets. In spite of this, however, these fisheries are not cultivated to anything like so high a degree as they might be. Still, the num ber of men engaged in the salmon fisheries in Ireland is over 13,000, the estimated value of the salmon exported being from $700,000 to $950,000 annually. The principal sea fisheries of Ireland are those of herring and mackerel. The herring fisheries in the Irish waters are prosecuted chiefly on the east coast by Irish boats from Howth, Arklow and other places on the Irish Coast, and by a fleet of vessels from Cornwall, Scotland, and the Isle of Man. The number of boats engaged in this branch of the sea fishery is much smaller than in Scotland, from which considerable quantities of cured herrings are im ported. The total number of vessels engaged in the sea fisheries (1914) was 5,290, with a total net tonnage of 27,880; the number of men and boys employed being about 18,000. The native fishermen successfully compete with their rivals, yet the sea fisheries of Ireland on the whole have much declined, as shown by the decrease from 55430 hands and 13,483 Loafs employed in 1860, to the figures just given. A large number of Irishmen are employed in the fish eries around the British coasts. See GREAT BRITAIN — FISHERIES.