We have abundant evidence that, just at the period when those great movements were commencing which resulted in the formation of the great Alpine and Himalayan geanticlinal, earth-fissures were being opened upon either side of the latter from which volcanic outbursts took place. At the period when the most violent mountain-forming movements occurred, these fissures were in their most active condition, and at this time two great volcanic belts stretched east and west, on either side of, and parallel to, the great Alpine chain. The Northern volcanic band was formed by the numerous vents, now all extinct, in Auvergne, Central Germany, Bohemia, and Hungary, and was probably continued in the volcanoes of the Thian Shan and Mantchouria. The Southern volcanic band was formed by the numerous vents of the Iberian and Italian peninsulas, and the islands of the Mediterranean, and were continued to the eastward by those of Asia Minor, Arabia, and the North Indian Ocean. As the earth-movements which produced the geanticlinal died away, the volcanic energy along these parallel volcanic bands died away at the same time. In studying the geology of Central and Southern Europe, no fact comes out more strikingly than that of the synchronism between the earth-movements by which the geanticlinal of the Alps was formed, and the volcanic manifestations which were exhibited along lines of fissure parallel to that geanticlinal. The earth-movements and the volcanic outbursts both commenced in the Oligocene period, gradually attained their maximum in the Miocene, and as slowly declined in the Pliocene. [Sidenote: SCULPTURING OF ALPS BY DENUDATION.]