308 HISTORICAL PALAEONTOLOGY. 



district known as the " Mauvaises Terres." They have a 

 thickness of 1000 feet or more, and contain numerous remains 

 of Mammals. They are of lacustrine origin, and are believed 

 to be of the age of the Lower Miocene. Upon the whole, 

 about from 1 5 to 30 per cent of the Mollusca of the American 

 Miocene are identical with existing species. 



In addition to the regions previously enumerated, Miocene 

 strata are known to be developed in Greenland, Iceland, Spitz- 

 bergen, and in other areas of less importance. 



The life of the Miocene period is extremely abundant, and, 

 from the nature of the deposits of this age, also extremely 

 varied in its character. The marine beds of the formation 

 have yielded numerous remains of both Vertebrate and Inver- 

 tebrate sea-animals ; whilst the fresh-water deposits contain 

 the skeletons of such shells, fishes, &c., as now inhabit rivers 

 or lakes. Both the marine and the lacustrine beds have been 

 shown to contain an enormous number of plants, the latter 

 more particularly ; whilst the Brown Coals of the formation 

 are made up of vegetable matter little altered from its original 

 condition. The remains of air-breathing animals, such as 

 Insects, Reptiles, Birds, and Mammals, are also abundantly 

 found, more especially in the fresh-water beds. 



The plants of the Miocene period are extraordinarily num- 

 erous, and only some of the general features of the vegetation of 

 this epoch can be indicated here. Our chief sources of informa- 

 tion as to the Miocene plants are the Brown Coals of Germany 

 and Austria, the Lower and Upper Molasse of Switzerland, 

 and the Miocene strata of the Arctic regions. The lignites of 

 Austria have yielded very numerous plants, chiefly of a tropical 

 character one of the most noticeable forms being a Palm of 

 the genus Sabal (fig. 234, B), now found in America. The 

 plants of the Lower Miocene of Switzerland are also mostly 

 of a tropical character, but include several forms now found 

 in North America, such as a Tulip-tree (Liriodendron} and a 

 Cypress (Taxodiuni). Amongst the more remarkable forms 

 from these beds may be mentioned Fan-Palms (Chamarops, 

 fig 234, A), numerous tropical ferns, and two species of Cin- 

 namon. The plant-remains of the Upper Molasse of Switzer- 

 land indicate an extraordinarily rank and luxuriant vegetation, 

 composed mainly of plants which now live in warm countries. 

 Among the commoner plants of this formation may be enume- 

 rated many species of Maple (Acer), Plane-trees (Platanus 

 fig. 235), Cinnamon-trees (fig. 236), and other members of the 

 Lauracece, many species of Proteaccce (Banksia, Grevillea, &c.), 

 several species of Sarsaparilla (Smilax], Palms, Cypresses, &c. 



