Page:Geology and Mineralogy considered with reference to Natural Theology, 1837, volume 1.djvu/387

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BROWN-COAL AND LIGNITE
383

importance for fuel, but very perfect remains of vegetables are dispersed in great abundance through the marly slates and limestone quarries which are worked there, and afford the most perfect history of the vegetation of the Miocene Period, which has yet come within our reach.[1]

  1. I have recently been favoured by Professor Braun of Carlsruhe, with the following important and hitherto unpublished catalogue, and observations on the fossil plants found in the Freshwater formation of Œningen, which has been already spoken of in our account of fossil fishes. The plants enumerated in this catalogue, were collected during a long series of years by the inmates of a monastery near Œningen, on the dissolution of which they were removed to their present place in the Museum of Carlsruhe. It appears by this catalogue that the plants of Œningen afford examples of thirty-six species belonging to twenty-five genera of the following families.
    "Families. Genera. Species. Genera. Species.
    Polypodiaceæ 2 2 Cryptogamiæ, total 4 4
    Equisitaceæ 1 1
    Lycopodiaceæ 1 1
    Coniferæ 2 2 Gymnospermiæ 2 2
    Gramineæ 1 1 Monocotyledons 3 3
    Najadeæ 2 2
    Amentaceæ 5 5 Dicotyledons 16 27
    Juglandeæ 1 2
    Ebenaceæ 1 1
    Tiliaceæ 1 1
    Acerineæ 1 5
    Rhamneæ 1 2
    Leguminoseæ 2 2
    Dicotyledons of doubtful families
    4 4

    This table shows the great preponderance of Dicotyledonous plants in the Flora of Œningen, and affords a standard of comparison with those of the Brown-coal of other localities in the Tertiary series. The greater number of the species found here correspond with those in the Brown-coal of the Wetteraw and vicinity of Bonn.

    Amid this predominance of dicotyledonous vegetables, not a single herbaceous plant has yet been found excepting some fragments of Ferns and Grasses, and many remains of aquatic plants: all the rest, belong to Dicotyledonous, and Gympospermous ligneous plants.

    Among these remains are many single leaves, apparently dropped in the natural course of vegetation; there are also branches with leaves on them, such as may have been torn from trees by stormy weather; ripe seed vessels; and the persistent calix of many blossoms.

    The greater part of the fossil plants at Œningen (about two thirds) belong to Genera which still grow in that neighbourhood; but their species differ, and correspond more nearly with those now living in North America, than with any European species, the fossil Poplars afford an example of this kind.

    On the other hand there are some Genera, which do not exist in the present Flora of Germany, e. g. the Genus Diospyros; and others not in that of Europe, e. g. Taxodium, Liquidambar, Juglans, Gleditschia.

    Judging from the proportions in which their remains occur, Poplars, Willows, and Maples were 'the predominating foliaceous trees in the former Flora of Œningen. Of two very abundant fossil species, one, (Populus latior,)resembles the modern Canada Poplar; the other, (Populus ovalis) resembles the Balsam Poplar of North America.

    The determination of the species of fossil Willows is more difficult. One of these (Salix angustifolia) may have resembled our present Salix viminalis.

    Of the genus Acer, one species may be compared with Acer campestre, another with Acer pseudo plat anus; but the most frequent species, (Acer pro tens urn,) appears to correspond most nearly with the Acer dasycarpon of North America; to another species, related to Acer negundo, Mr. Braun gives the name of Acer trifoliatum. A fossil species of Liquidambar (L. europeum, Braun.) differs from the living Liquidambar styracifluum of America, in having the narrower lobes of its leaf terminated by longer points, and was the former representative of this genus in Europe. The fruit of this Liquidambar is preserved, and also that of two species of Acer and one Salix.

    The fossil Linden Tree of Œningen resembled our modern large-leaved Linden tree (Tilia grandillora.)

    The fossil Elm resembled a small leaved form of Ulmis campestris.

    Of two species of Juglans, one (J. falcifolia) may be compared with the American J. nigra; the other, with J. Alba, and, like it, probably belonged to the division of nuts with bursting' external shells, (Carya Nuttal.)

    Among the scarcer plants at Œningen, is a species of Diospyros (D. brachysepala.) A remarkable calyx of this plant is preserved, and shows in its centre, the place where the fruit separated itself: it is distinguished from the living Diospyros lotus of the South of Europe by blunter and shorter sections.

    Among the fossil shrubs are two species of Rhamnus; one of these (R. multinervis, Braun) resembles the R. alpinus, in the co station of its leaf. The second and most frequent species, (R. terminal is, Braun) may with regard to the position and co station of its leaves, be compared in some degree with R. catharticus, but differed from all living species in having its flowers placed at the tips of the plant.

    Among the fossil Leguminous plants is a leaf more like that of a fruticose Cytisus than of any herbaceous Trefoil.

    Of a Gleditschia, (G. podocarpa, Braun) there are fossil pinnated leaves and many pods; the latter seem, like the G. Monasperma of North America, to have been single seeded, and are small and short, with a long stalk contracting the base of the pod.

    With these numerous species of foliaceous woods, are, found also 3 few species of Coniferæ. One species of Abies ls still undetermined; branches and small cones of another tree of this family (Taxodium europeum, Ad. Brong.) resemble the Cypress of Japan (Taxodium Japonicum.)

    Among the remains of aquatic plants are a narrow-leaved Potamogeton; and an Isoetes, similar to the I. lacustris now found in small lakes of the Black Forest, but not in the Lake of Constance.

    The existence of Grasses at the period when this formation was deposited, is shown by a well preserved impression, of a leaf, similar to that of a Triticum, turning to the right, and on which the co station is plainly expressed.

    Fragments of fossil Ferns occur here, having a resemblance to Pteris aquilina and Aspidium Filix mas.

    The remains of Equisetum indicate a species resembling E. palustre.

    Among the few undetermined remains are the five-cleft and beautiful veined impressions of the Calyx of a blossom, which are by no means rare at Œningen.

    No remains of any Rosaceæ have yet been discovered at this place." Letter from Prof. Braun to Dr. Buckland, Nov. 25, 1835.

    In addition to these fossil Plants, the strata at Œningen contain many species of freshwater Shells, and a remarkable collection of fossil Fishes, which we have before mentioned, P. 285. In the family of Reptiles they present a very curious Tortoise, and a gigantic aquatic Salamander, more than three feet long, the Homo Diluvii testis of Scheuchzer. A Lagomys and fossil Fox have also been found here. (See Geol. Trans. Lond. N. S. vol. iii. p. 287.

    In Oct. 1835, I saw in the Museum at Leyden, a living Salamander three feet long, the first ever brought alive to Europe, of a species nearly allied to the fossil Salamander of Œningen. This animal was brought by Dr. Siebold from a lake within the crater of an extinct volcano, on a high mountain in Japan. It fed greedily on small fishes, and frequently cast its epidermis.