In the Gault, near Folkestone, an interesting association of coniferous fruits has been found, consisting of two species of Sequoia, along with two of Pinus. The pines belong to the same group as those which now grow with the Wellingtonias in California, showing the remarkable fact that the coniferous vegetation of the high lands of the Upper Cretaceous period had a facies similar to that now existing in the mountains on the west of North America. We figure both the species of Sequoiites—viz. S. ovalis (Fig. 91), a large cone, and S. Gardneri ([Plate II. Fig. 7]). In the present day there are two species of the genus Sequoia—viz. S. gigantea (Wellingtonia gigantea) and S. sempervirens.[20] In the Lower Greensand a remarkably fine cone belonging to the same group as the Cedar has been found. This is the Pinites Leckenbyi ([Plate II. Fig. 4]). A section exhibits the seeds in their true position, some of which are preserved so as to exhibit the form and position of the embryo.

Fig. 92.

Fig. 92. Pinites ovatus (Zamia ovata of Lindley and Hutton), an ovate cone with a truncated base and obtuse apex, nearly allied to the stone-pine.

The Tertiary period is characterised by the abundance of Angiospermous Dicotyledons and of Monocotyledons, more especially of Palms. By this it is distinguished from the more ancient periods. Angiosperms at this period greatly exceed Gymnosperms. Cycadaceæ are very rare, if not completely wanting, in the European Tertiary strata, and the Coniferæ belong to genera of the temperate regions. In the lower Tertiaries Carruthers has found a fossil Osmunda, and the existence of a group of Pines having cones with a very thick apophysis. From their remarkable external aspect, these cones had been considered to be Cycadean, but their internal structure indicates that they are coniferous. Pinites ovatus is one of these cones (Fig. 92). The Cupressineæ are found in the Tertiary beds only. Taxodieæ are represented by Sequoiites ([Plate II. Fig. 7]) in the Cretaceous and Eocene strata. Peuce australis of Van Diemen's Land and P. Pritchardi of Ireland are Tertiary plants. The Peuce of Eigg (P. Eggensis), according to Geikie, is also Tertiary, and not Oolitic. Isoetes is mentioned by Schimper as a Tertiary genus. Although the vegetation throughout the whole of the Tertiary period presents pretty uniform characters, still there are notable differences in the generic and specific forms, and in the predominance of certain orders at different epochs. Brongniart does not entirely agree with Unger as to these epochs. Many of the formations classified by Unger in the Miocene division he refers with Raulin to the Pliocene. He divides the Tertiary period, as regards plants, into the Eocene, Miocene, and Pliocene epochs, and gives the following comparative results from an examination of their floras:—

Classes and Sub-Classes.Eocene Epoch.Miocene Epoch.Pliocene Epoch.
Thallogenæ1666
Acrogenæ1747
Monocotyledones33264
Dicotyledones—
Gymnospermæ401931
Angiospermæ10378164
209133212

[Flora of the Eocene Epoch.]

In the Eocene formation the fossil fruits of the Isle of Sheppey increase the number of Phanerogamous plants, only a small proportion of which have as yet been described. This is an exceptional locality, and the deposit in which the fruits occur is probably the silt found at the mouth of a large river which flowed, like the Nile, from tropical regions towards the north. The number of plants as given by Brongniart is much smaller than that mentioned by Unger (p. 23). The latter includes in his enumeration a considerable amount of uncertain species.

Fig. 93.