Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/468

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358
PROCEEDINGS OF THE GEOLOGICAL SOCIETY.


(1) Basalt, 15 feet; (2) brown earth, 3 inches; (3) layer of impure earthy lignite, 8 to 12 inches; (4) brown and red bole or earth becoming red at the lower portion and passing into the plant-layer, no. 5; (5) plant-layer, 4 to 8 inches thick; (6) conglomerate bed, principally composed of ironstone nodules, probable thickness 10 or 12 feet; (7) rails resting on basalt.

The condition in which these plant-remains are found is not quite so favourable for determination as that of those from the Isle of Mull: the fossils under consideration occur in a red clay, some parts of which are more or less arenaceous; the impressions, although preserving the outline of the leaf, do not in many cases show clearly the important character of venation[1].

In addition to the specimens obtained by Mr. Du Noyer, a large number were collected by Mr. M'Henry, also of the Geological Survey, many of them from another part of the same railway-cutting; and although the series contains some well-defined examples of the vegetation of the period, it does not include a very great variety of forms.

The only specimen in which the generic character can be decided upon with any degree of certainty is that of a Fir-cone, named by me Pinus Plutonis, Pl. XV. fig. 1, a & b; this cone may be compared with that of the Pinus pinaster or Cluster Pine, especially to the variety maritimus, the fruit of which is composed of large and hard scales[2]; in the collection are also many fragments of the branches of another coniferous tree, the stem of which was covered with small elongated tapering leaves, Pl. XV. fig. 4, a & b. I have named this Sequoia Du Noyeri in memory of the lamented gentleman to whom we owe the discovery of this plant-bed. It resembles very closely Sequoia Sternbergi, Heer[3], from Iceland, but differs in the relative size and closer arrangement of the leaves on the stem. The only recent example with which I had an opportunity of comparing it was Sequoia sempervirens, the Red Cedar of California; the more open arrangement of the leaves on the branches of that tree offers, however, a closer comparison with the fossil plant from the Isle of Mull, doubtfully referred by Professor Forbes to Taxites[4]; I think

  1. In reply to a remark made during the discussion on this paper, at the reading of which the author was unavoidably absent, he begs to state that whilst fully impressed with the desirability of using great caution in the determination of species from insufficient data, he feels quite justified in applying names to such specimens as the Sequoia, Pinus, and Cupressites, with respect to the generic affinities of which there can be but little doubt; the remaining specimens, principally leaves, he did not attempt to identify positively, but, after careful comparison with the works of Unger, Massalongo, Heer, &c., merely ventured to suggest the possibility of their belonging to certain genera and species figured by those authors from probably contemporaneous deposits. In reference to this subject the author would beg to refer to Prof. Forbes's remarks on the fossil plants he named from the Isle of Mull, anticipating an objection of this kind, in his note to the Duke of Argyll's paper before cited.
  2. These cones, which must have been at least 3 inches long, are called by the workmen employed in excavating the iron-ore "Firs;" they occur in a black carbonized condition, and are said by them to be not unfrequent.
  3. Flora Fossilis Arctica, p. 140, pl. 24. fig. 9.
  4. Quart. Journ. Geol. Soc. vol. vii. pl. 2. fig. 1.