Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/404

 of the Upper Devonian, while those from Ohio are from a marine limestone, belonging to the lower part of the Middle Devonian.

1. Caulopteris Lockwoodi, n. sp.

(Plate XII. figs. 1 to 3.)

Trunk from two to three inches in diameter, rugose longitudinally. Leaf-scars broad, rounded above, and radiatingly rugose, with an irregular scar below, arranged spirally in about five ranks ; vascular bundles not distinctly preserved. Petioles slender, much expanded at the base, dividing at first in a pinnate manner, and afterwards dichotomously. Ultimate pinnae with remains of numerous, apparently narrow pinnules.

This stem is probably the upper part of one or other of the species of Psaronius found in the same bed (P. erianus, Dawson, MS., and P. textilis, Dawson, MS. *). It appears to have been an erect stem imbedded in situ in sandstone, and preserved as a cast. The stem is small, being only two inches, or a little more, in diameter. It is coarsely wrinkled longitudinally, and covered with large leaf-scars (fig. 2) each an inch in diameter, of a horseshoe-shape. The petioles, five of which remain, separate from these scars with a distinct articulation, except at one point near the base, where probably a bundle or bundles of vessels passed into the petiole. They retain their form at the attachment to the stem, but a little distance from it they are flattened. They are inflated at the base, and somewhat rapidly diminish in size. The leaf-scars vary in form, and are not very distinct, but they appear to present a semicircular row of pits above, largest in the middle. From these there proceed downward a series of irregular furrows, converging to a second and more obscure semicircle of pits, within or below which is the irregular scar or break above referred to. The attitude and form of the petioles will be seen from fig. 1.

The petioles are broken off within a few inches of the stem ; but other fragments found in the same beds appear to show their continuation, and some remains of their foliage. One specimen shows a series of processes at the sides, which seem to be the remains of small pinnae, or possibly of spines on the margin of the petiole. Other fragments show the division of the frond, at first in a pinnate manner, and subsequently by bifurcation ; and some fragments show remains of pinnules, possibly of fertile pinnules. These are very indistinct, but would seem to show that the plant approached, in the form of its fronds and the arrangement of its fructification, to the Cyclopterids of the subgenus Aneimites, one of which (Aneimites acadica), from the Lower Carboniferous of Nova Scotia, I have elsewhere described as probably a tree fern†. The fronds were evidently different from those of Archoeo-


 * Memoir on Devonian Flora, Proceedings of Royal Society, May 1870.

† Quart. Journ. Geol. Society, 1860.