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Show 224 MIOCENE PERIOD· (Ch. XVI. m• S• • .1.': d ,.b d ere shown to be contemporaneous 1c1l y, be1ore escu e ' w with newer Pliocene strata*· . Auvergne-rT Te[ a y. -We believe that part o.f the volc.a mc eruptt.o ns of A uvergnc took place during the Mio. cene p. cnod ; those, for examp1 e , wh ich cover' or are interstratlfied with .t he alluvl·l lms men t'w ne d 1'n this chapter' and . some of the ancient basa1 t 1· c capp·m gs of hills in Au. vergne. , whiCh repose on gravel characten·z ed bY S'lm ilar orgamc remams. A part also of the 1· gneous roc k s of Velay belonOo' to this epoch, but to th. ese we shall agam• rett:'e r w} 1 en we treat more full. y of the volc.a mc rocks of Central F 1. a nce ., the older part of wh1eh are referr1ble to the Eocene period. • Sedgwick and Murcht·s on, G eo 1• T ra ns • Second Series, vol. iii. p. 400.- Daubeny, Extinct Volcanos, P· 92. CHAPTER XVIl. Eocene period- Fresh-water formations -Central France -Map- Limagne cl'Auvergne-Saudstone and conglomerate-Tediary Red marl and sandstone like the secondary 'now rcu ~andstone'-Grecn and white foliateu marlsIndusinl limestone-Gypseous marls-General arrangement anu origin of the Travertin-Fresh-water formation of the Limagne-Puy en V elay-Analogy of the strata to those of Auvergne-Cantal-Resemblanco of Aurillac limestone and its flints to our upper chalk-Proofs of the gradual deposition of marlConcluding Remarks. EOCENE FRESH-WATER FORMATIONS. WE have now traced back the history of the European formations to that period when the seas and lakes were inhabited by a few only of the existing specieR of testacea~ a period which we have designated Eocene, as indicating the dawn of the present state of the animate creation. But although a small number only of the living species of animals were then in being, there are ample grounds for inferring that all the great classes of the animal kingdom, such as they now exist, were then fully represented. In regard to the testacea, indeed, it is no longer a matter of inference, for 1400 species of this class have been obtained from that small number of detached Eocene deposits which have hitherto been examined in Europe. The celebrated Paris basin, the position of which was pointed out in the former part of this volume, (see wood-cut, p. 16) first presents itself, and seems to claim our chief attention when we treat of the phenomena of this era. But in order more easily to explain to the student the peculiar nature and origin of that gl'Oup, it will be desirable, nrst, to give a brief sketch of certain deposits of Central France, which afford many interesting points of analogy, both in organic remains and mineral composition, and where the original circumstances unde1~ which the strata were accumulated may more easily be discerned. Vo1., III. Q |