countless leaves of which were imbedded in mud, and together with them, at some points, a species of reed, _Arundo_, which was very common. One of the most characteristic shrubs is a papilionaceous and leguminous plant of an extinct genus, called by Heer _ Podogonium_, of which two species are known. Entire twigs have been found with flowers, and always without leaves, as the flowers evidently came out, as in the poplar and willow tribe, before any leaves made their appearance. Other specimens have been obtained with ripe fruits accompanied by leaves, which resemble those of the tamarind, to which it was evidently allied, being of the family Cæsalpineæ, now proper to warmer regions. Fig. 138: Acer trilobatum. The Upper Miocene flora of Œningen is peculiarly important, in consequence of the number of genera of which not merely the leaves, but, as in the case of the _Podogonium_ just mentioned, the fruit also and even the flower are known. Thus there are nineteen species of maple, ten of which have already been found with fruit. Although in no one region of the globe do so many maples now flourish, we need not suspect Professor Heer of having made too many species in this genus when we consider the manner in which he has dealt with one of them, _Acer trilobatum_, Figs. 139 and 140. Of this plant the number of marked varieties figured and named is very great, and no less than three of them had been considered as distinct species by other botanists, while six of the others might have laid claim, with nearly equal propriety, to a like distinction. The common form, called _Acer trilobatum_, Fig. 139, may be taken as a normal representative of the Œningen fossil, and Fig. 140, as one of the most divergent varieties, having almost four lobes in the leaf instead of three. Fig. 140: Acer trilobatum. Among the conspicuous genera which abounded in the Miocene period in Europe is the plane-tree, _Platanus,_ the fossil species being considered by Heer to come nearer to the American _ P. occidentalis_ than to _P. orientalis_ of Greece and Asia Minor. In some of the fossil specimens the male flowers are preserved. Among other points of resemblance with the living plane-trees, as we see them in the parks and squares of London, fossil fragments of the trunk are met with, having pieces of their bark peeling off. Platanus aceroides. The vine of Œningen, _Vitis teutonica_, Ad. Brong, is of a North American type. Both the leaves and seeds have been found at Œningen, and bunches of compressed grapes of the same species have been met with in the brown coal of Wetteravia in Germany. No less than eight species of smilax, a monocotyledonous genus, occur at Œningen and in other Upper Miocene localities, the flowers of some of them, as well as the leaves, being preserved; as in the case of the very common fossil, _S. sagittifera_, Fig. 142, _a._