Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/470

This page has been proofread, but needs to be validated.
360
PROCEEDINGS OF THE GEOLOGICAL SOCIETY.

distinct species resembling those of some of the smaller Carabidæ, one of them (fig. 14) having an arrangement of puncta like that on some of the weevils or small diamond-beetles. The only two specimens observed are very minute, and are figured on Pl. XIV. figs. 14, 15.

So far as can be judged from a preliminary examination such as this, these plant-remains from between the Basalts of Antrim appear to differ as a group from those obtained in corresponding beds at the Isle of Mull.

The majority of the plants from the Ardtun Head, as stated by Professor Forbes, consisted of palmate leaves having three or more lobes, referred by him to Platanites[1], from their resemblance to the Plane or Sycamore. Throughout the collection from the north of Ireland there is at present no evidence of any leaves of this form, the majority being simply ovate or lanceolate with entire margins; there is, however, considerable resemblance between some of these and the leaves he figures under the name of Rhamnites[2].

A generic identity may also be found to exist between the plant I have referred to Sequoia and that doubtfully assigned by Forbes to Taxites[3]; in the former, however, the leaves are more numerous, surrounding the stem more closely; and it approaches so nearly Sequoia Sternbergi, Heer, that I have but little hesitation in including it in the same genus.

No indication of Ferns or Equisetum-like plants, such as were described from the leaf-beds of the Isle of Mull, has yet been observed amongst these Antrim fossils. The presence of large fragments of wood is also a distinctive feature amongst these plants from the north of Ireland, the Duke of Argyll in his description having specially remarked on the absence of any fragments of trees larger than the merest twig in the plant-deposits of the Isle of Mull.

Although the specimens are not generally in a sufficiently perfect state of preservation for specific identification, there is perhaps enough to indicate their alliance with mid-European forms; and though not specifically identical with those from the Isle of Mull, like them, they most probably belong to a corresponding epoch in geological time, that of the Miocene.

Description of the Species named.

Pinus Plutonis, Baily. Plate XV. fig. 1, a & b, and fig. 2.

Fruit or cone of a Fir, ovate and elongate, composed of large broad scales, each marked with a semicircular and central ridge; base of scales striated. Length of cone about 3 inches; diameter at widest part 11/4 inch. The separate scale (fig. 1 b) and the section on the same Plate (fig. 2) most probably belong to one species.

  1. Platanites hebridicus, Forbes, Quart. Journ. Geol. Soc. vol. vii. p1. iii. f. 5, and pl. iv. f. 1. Sir C. Lyell suggests the identity of this species with P. aceroides, 'Elements of Geology' (1865), p. 240.
  2. Quart. Journ. Geol. Soc., vol. vii. pl. iii. figs. 2, 3, 4.
  3. See ante p. 359, and footnote.