Page:Proceedings of the Royal Society of London Vol 60.djvu/451

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of Fossil Cone from the Calciferous Sandstone.
419

phylls, each of which bears a number of sporangia. It became evident that this cone must be placed in a new genus, and the conclusion arrived at from the study of the peduncle was thus confirmed.

Mr. Kidston most generously handed over his sections to me for examination and description, and also obtained for me from the owner the remains of the original block, from which I have had a number of additional sections prepared.

Only a single specimen of the cone is at present known. Before cutting sections, the piece, which includes the base but not the apex of the strobilus, was about 2 inches long. It was found at Pettycur, near Burntisland, in 1883, by Mr. James Bennie of Edinburgh. The specimen is calcified, and its preservation is remarkably perfect, so that the whole structure is well shown, though the complexity of its organisation renders the interpretation in some respects difficult.

The cone in its present somewhat flattened condition measures about 5 cm. by 2’3 cm. in diameter. The diameter in its natural state would have been at least 3'5 cm. That of the axis is about 7 mm., exactly the same as that of Williamson’s peduncle. Thus the extreme length of the sporophylls, which have on the whole an approximately horizontal course, is about l -4 cm.

The sporophylls are arranged in somewhat crowded verticils, fourteen of which were counted in a length of an inch, 2‘5 cm. There are twelve leaves in each whorl, and the members of successive whorls are accurately superposed, a fact which is shown with the greatest clearness in tangential sections of the cone. This is evidently a point of great significance in considering the affinities of the fossil.

The sporophylls themselves have a remarkably complex form. Each sporophyll at its insertion on the axis, consists of a short basal portion or phyllopodium; the bases of the sporophylls belonging to the same verticil are coherent. The sporophyll branches immediately above its base, dividing into a superior and an inferior lobe, which lie directly one above the other in the same I’adial plane. Almost at the same point, each of the lobes subdivides in a palmate manner into three segments, which assume a horizontal course, whereas the common phyllopodium lias an upward inclination. It is probable that sometimes, especially at the base of the cone, there may be two instead of three segments to each lobe. As a rule, however, each sporophyll consists of six segments, of which three belong to the superior (ventral or posterior) and three to the inferior (dorsal or anterior) lobe.

The segments are of two kinds—sterile and fertile. Both alike consist of a long, straight, slender pedicel, running out horizontally, and terminating at the distal end in a thick laminar expansion. The sterile segments are the longer, and in each the lamina bears an