IV. _Aufschuttungsgebirge_--Mountains of accumulation. V. _Flachboden_--Plateaux. (a) _Abrasionsplatten_--Abraded plateaux. (b) _Marines Flachland_--Plain of marine erosion. (c) _Schichtungstafelland_--Horizontally stratified tableland. (d) _Ubergusstafelland_--Lava plain. (e) _Stromflachland_--River plain. (f) _Flachboden der atmospharischen Aufschuttung_--Plains of aeolian formation. VI. _Erosionsgebirge_--Mountains of erosion. Mountain forms. From the morphological point of view it is more important to distinguish the associations of forms, such as the _mountain mass_ or group of mountains radiating from a centre, with the valleys furrowing their flanks spreading towards every direction; the _mountain chain_ or line of heights, forming a long narrow ridge or series of ridges separated by parallel valleys; the _dissected plateau_ or highland, divided into mountains of circumdenudation by a system of deeply-cut valleys; and the _isolated peak_, usually a volcanic cone or a hard rock mass left projecting after the softer strata which embedded it have been worn away (Monadnock of Professor Davis). Distribution of mountains. The geographical distribution of mountains is intimately associated with the great structural lines of the continents of which they form the culminating region. Lofty lines of fold mountains form the "backbones" of North America in the Rocky Mountains and the west coast systems, of South America in the Cordillera of the Andes, of Europe in the Pyrenees, Alps, Carpathians and Caucasus, and of Asia in the mountains of Asia Minor, converging on the Pamirs and diverging thence in the Himalaya and the vast mountain systems of central and eastern Asia. The remarkable line of volcanoes around the whole coast of the Pacific and along the margin of the Caribbean and Mediterranean seas is one of the most conspicuous features of the globe. Functions of land forms. Land waste. Glaciers.