ABSTRACT
The name Altaids was given by Suess to a system of mountain folds that comprises the main portion of Eurasia extending from the Vertex, or according to Gregory’s expression, from the Nucleus of the Russian Altai through the central part of Asia to the mountainous plateau of Tibet. In the East Indies the extremities of this system comprise the Sunda Arc as far east as the Banda Sea. To the W. they include not only the remote branches of the Variscan and Armorican chains of Middle Europe, but also, across the Atlantic Ocean, the so-called American Altaids in the Appalachians, still traceable as far as the hills of Oklahoma, W. of the Mississippi. Even the Alpids, that is the Kainozoic mountain ranges of the Mediterranean, are regarded by Suess as a posthumous group of the Altaids, and their origin is attributed to the pressure of the older Altaid framework surrounding them. It should be borne in mind that when this classification was brpught forward, stronger emphasis was laid on the importance in structural geology of trend-lines of strata than on the morphological outlines.
