Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/519

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From the Lower Trias (Gres bigarre) of France, the following : —

Chelepteris vogesiaca, Schimp. Traite Pal. Veg. vol. i. p. 702. Ch. Voltzii, Schimp. Tr. Pal. Veg. vol. i. p. 703. Ch. micropeltis, Schimp. Tr. Pal. Veg. vol. i. p. 703.

Bathypteris Lesangeana, Schimp. & Moug. Monogr. Pl. Foss. des Vosges, p. 67.

And from the Keuper, near Wurzburg : —

Chelepteris macropeltis, Schenk, in Von Meyers Palaeontogr. vol. xi. p. 304.

Bathypteris strongylopeltis, Schenk, in Verh. Phys. Med. Gesellsch. Wurzb. vol. viii. p. 212.

EXPLANATION OF PLATES XXIV. & XXV.

Plate XXIV.

Figs. 1-3. Osmundites Dowkeri, Carr.

Figs. 1 & 2. Drawings of the outer surfaces of the specimen. Fig. 1 is the surface which has been most rubbed, and exhibits the bases of the petioles near their origin. Fig. 2 represents the less-worn surface, with larger petioles and adventitious roots, The lunate vascular bundle is shown at the ends of some of the petioles. Fig. 3 is a transverse section, showing the position of the axis and of the petioles and roots.

Figs. 4-6. Osmunda regalis, Linn.

Fig. 4. Outer surface of the caudex after the adventitious roots have been cut away. Fig. 5. Transverse section, showing the axis, petioles, and roots. Fig. 6. Transverse section of the axis, showing the meshes in the vascular cylinder. All the figures are of the natural size.

Plate XXV.

Figs. 1, 3, & 4. Osmundites Dowkeri, Carr.

Fig. 1. Section of a portion of the centre of the stem, showing : — a, the central cellular tissue ; b, the vascular cylinder with the meshes through which have passed the vascular bundles to the leaves ; c, the tissues of two petioles or leaf-stalks ; d, the dark -coloured parenchyma surrounding the axis ; e, two adventitious roots. Fig. 3. A few cells, showing the starch granules, and the mycelium of the fungus. Fig. 4. Transverse section of a petiole, showing : — a, the boundary of the petiole ; b, the parenchyma surrounding the vascular axis ; and, e, the parenchyma of the wing of the petiole.

Figs. 2 & 5. Osmunda regalis, Linn.

Fig. 2. Transverse section of part of the axis, showing : — a, the central cellular tissue ; b, the vascular cylinder ; c, two petioles ; d, the parenchyma surrounding the axis ; e, a root springing from the vascular cylinder. Fig. 5. Longitudinal section of a petiole, showing : — a, the boundary of the petiole ; b, the parenchyma ; c, the scalariform tissue ; d, the parenchyma separating the two extremities of the vascular bundle ; e, the parenchyma of the wing of the petiole.

Discussion.

Mr. W. W. Smyth, in calling on those present for remarks on the paper, commented on the very remarkable manner in which the minutest details of the original plant had become silicified. Mr. Etheridge mentioned the discovery of fossil fern-stems of somewhat similar character at Bromsgrove.

Prof. Ramsay suggested the possibility of the fossil having been derived from a bed even higher than the Thanet Sands. He thought the rarity of such delicate structures being perfectly preserved by