M. Ad. Brongniart places the commencement of dicotyledonous gymnosperm plants in this age. The characteristics of this Flora consist in numerous Ferns, constituting genera now extinct, such as _Anomopteris_ and _Crematopteris_. The true _Equiseta_ are rare in it. The Calamites, or, rather, the _Calamodendra_, abound. The gymnosperms are represented by the genera _Conifer_, _Voltzia_, and _Haidingera_, of which both species and individuals are very numerous in the formation of this period. Among the species of plants which characterise this formation, we may mention _Neuropteris elegans_, _Calamites arenaceus_, _Voltzia heterophylla_, _Haidingera speciosa_. The _Haidingera_, belonging to the tribe of _Abietinæ_, were plants with large leaves, analogous to those of our _Damara_, growing close together, and nearly imbricated, as in the _Araucaria_. Their fruit, which are cones with rounded scales, are imbricated, and have only a single seed, thus bearing out the strong resemblance which has been traced between these fossil plants, and the Damara. The _Voltzias_ (Fig. 84), which seem to have formed the greater part of the forests were a genus of Cupressinaceæ, now extinct, which are well characterised among the fossil Conifers of the period. The alternate spiral leaves, forming five to eight rows sessile, that is, sitting close to the branch and drooping, have much in them analogous to the _Cryptomerias_. Their fruit was an oblong cone with scales, loosely imbricated, cuneiform or wedge-shaped, and, commonly, composed of from three to five obtuse lobes. In Fig. 84 we have a part of the stem, a branch with leaves and cone. In his “Botanic Geography,” M. Lecoq thus describes the vegetation of the ancient world in the first period of the Triassic age: “While the variegated sandstone and mottled clays were being slowly deposited in regular beds by the waters, magnificent Ferns still exhibited their light and elegantly-carved leaves. Divers _Protopteris_ and majestic _Neuropteris_ associated themselves in extensive forests, where vegetated also the _Crematopteris typica_ of Schimper, the _Anomopteris Mongeotii_ of Brongniart, and the pretty _Trichomanites myriophyllum_ (Göppert). The Conifers of this epoch attain a very considerable development, and would form graceful forests of green trees. Elegant monocotyledons, representing the forms of tropical countries, seem to show themselves for the first time, the _Yuccites Vogesiacus_ of Schimper constituted groups at once thickly serried and of great extent. “A family, hitherto doubtful, appears under the elegant form of _Nilssonia Hogardi_, Schimp.; _Ctenis Hogardi_, Brongn. It is still seen in the _Zamites Vogesiacus_, Schimp.; and the group of the Cycads sharing at once in the organisation of the Conifers and the elegance of the Palms, now decorate the earth, which reveals in these new forms its vast fecundity. (See Fig. 72, p. 168.) [Illustration: Fig. 84.--Branch and cone of Voltzia restored.]