regarding as dicotyledonous. But they formed, whatever their true character, a very inconspicuous feature in the Oolitic flora; and not until the overlying Cretaceous System is ushered in do we find leaves in any considerable quantity decidedly of this high family; nor until we enter into the earlier Tertiaries do we succeed in detecting a true dicotyledonous tree. On such an amount of observation is this order of succession determined,--though the evidence is, of course, mainly negative,--that when, some eight or ten years ago, Dr. John Wilson, the learned Free Church missionary to the Parsees of India, submitted to me specimens of fossil woods which he had picked up in the Egyptian Desert, in order that I might if possible determine their age, I told him, ere yet the optical lapidary had prepared them for examination, that if they exhibited the coniferous structure, they might belong to any geologic period from the times of the Lower Old Red Sandstone downwards; but that if they manifested in their tissue the dicotyledonous character, they could not be older than the times of the Tertiary. On submitting them in thin slices to the microscope, they were found to exhibit the peculiar dicotyledonous structure as strongly as the oak or chestnut. And Lieutenant Newbold's researches in the deposit in which they occur has since demonstrated, on stratigraphical evidence, that not only does it belong to the great Tertiary division, but also to one of the comparatively modern formations of the Tertiary. [Illustration: Fig. 38 EQUISETUM COLUMNARE. (Nat. size.)] [Illustration: Fig. 39. CARPOLITHES CONICA. (Reduced one third.)] [Illustration: Fig. 40. CARPOLITHES BUCKLANDII.[10] (Reduced one third.)] [Illustration: Fig. 41. ACER TRILOBATUM.[11] (Miocene of OEningen.)] [Illustration: Fig. 42. ULMUS BRONNII.[12] (Miocene of Bohemia.)] [Illustration: Fig. 43. PALMACITES LAMANONIS. (A Palm of the Miocene of Aix.)]