THE MIOCENE PERIOD. 317 



In France, the Lower Miocene is represented in Auvergne, 

 Cantal, and Velay, by a great thickness of nearly horizontal 

 strata of sands, sandstone, clays, marls, and limestones, the 

 whole of fresh-water origin. The principal fossils of these 

 lacustrine deposits are Mammalia, of which the remains occur 

 in great abundance. In the valley of the Loire occur the 

 typical European deposits of Upper Miocene age. These are 

 known as the " Faluns, " from a provincial term applied to 

 shelly sands, employed to spread upon soils which are deficient 

 in lime; and the Upper Miocene is hence sometimes spoken 

 of as the " Falunian " formation. The Faluns occur in scat- 

 tered patches, which are rarely more than 50 feet in thickness, 

 and consist of sands and marls. The fossils are chiefly marine ; 

 but there occur also land and fresh-water shells, together with 

 the remains of numerous Mammals. About 25 per cent of the 

 shells of the Faluns are identical with existing species. The 

 sands, limestones, and marls of the Department of Gers, near 

 the base of the Pyrenees, rendered famous by the number of 

 Mammalian remains exhumed from them by M. Lartet, also 

 belong to the age of the Faluns. 



In Switzerland, between the Alps and the Jura, there occurs 

 a great series of Miocene deposits, known collectively as the 

 " Molasse, " from the soft nature of a greenish sandstone, 

 which constitutes one of its chief members. It attains a thick- 

 ness of many thousands of feet, and rises into lofty mountains, 

 some of which as the Rigi are more than 6000 feet in 

 height. The middle portion of the Molasse is of marine 

 origin, and is shown by its fossils to be of the age of the 

 Faluns; but the lower and upper portions of the formation 

 are mainly or entirely of fresh-water origin. The Lower 

 Molasse (of Lower Miocene age) has yielded about 500 species 

 of plants, mostly of tropical or sub-tropical forms. The Upper 

 Molasse has yielded about the* same number of plants, with 

 about 900 species of Insects, such as wood-eating Beetles, 

 Water-beetles, White Ants, Dragon-flies, &c. 



In Belgium, strata of both Lower and Upper Miocene age 

 are known, the former (Rupelian Clays} containing numerous 

 marine fossils; whilst the latter (Bolderberg Sands) have 

 yielded numerous shells corresponding with those of the 

 Faluns. 



In Austria, Miocene strata are largely developed, marine 

 beds belonging to both the Lower and Upper division of the 

 formation occurring extensively in the Vienna basin. The 



