"_1st, Sub-Cretaceous Epoch_.--In the subcretaceous marine lignites of the Isle of Aix, near La Rochelle, and of Pialpinson, in the department of the Dordogne; these are the most ancient beds of the Cretaceous formation, or the last of the Jurassic period. Here have been found only marine plants, wood, and branches of Coniferæ. "_2d_, In the chloriteous chalk or greensand of southern England, the neighbourhood of Beauvais and Maus; only Cycadeæ and marine plants have been observed there. "_3d_, In the same formation in Scania, where M. Nilson has observed leaves of Dicotyledons mixed with leaves of Cycadites. "_4th_, At Niederschoena, near Freyberg, in Saxony, beds, analogous to greensand or quadersandstein, containing fossils of considerable variety, Cycadeæ, Coniferæ, and Dicotyledons, particularly _Credneria_. "_5th_, In the quadersandstein of Bohemia and Silesia, at Blankenburg, at Teifenfurth, Teschen, &c., where this sandstone is characterised by the presence of dicotyledonous leaves of the genus _Credneria_, by Cyeadeæ, and particularly by Coniferæ of considerable variety, described by M. Corda in Reuss' work on the Chalk of Bohemia. "_6th_, In France, in the iron sands connected with the green sandstones, near Grand-Pré, in the department of Ardennes, where M. Buvignier has found two fossil vegetables of a very remarkable character, a stalk of an arborescent fern, and a cone previously observed in England in the same formation. "But in other places, and in beds belonging to epochs certainly different, this period has presented only marine vegetables; such more especially are those fucoidal sandstones or macigno, characterised by Chondrites targionii, æqualis, intricatus, &c., now designated by the name of fucoidal sandstone or flysch--the geological epoch of which has long been doubtful, but which observers seem to agree in considering as a distinct formation, superior to the chalk, and inferior to the most ancient beds of the Tertiary formations. "These fucoidal sandstones form a very distinct epoch, which hitherto appears to be characterised only by marine vegetables, and what, at least in a botanical point of view, would form the line of demarcation between the Cretaceous and Tertiary formations; for it is remarkable that the fuci found there in such great numbers have little connection with those of the Chalk, properly so called, and none whatever with those of the most ancient beds of the Tertiary formations, such as those of Monte-Bolca.