. Studies in fossil botany . Paleobotany. i66 STUDIES IN FOSSIL BOTANY Fig. 67). The characteristic feature of the Ulodendron stem consists in the presence of roundish scars,often of very large size, usually arranged alternately in two vertical rows, one row on each side of the stem. On the larger Ulodendra these scars have a diameter of from 4 to 6 inches. Within the scar, usually somewhat below the centre, is a print or stump, representing either the stalk or the woody cylinder of some lateral appendage. The scar as a whole is depressed, having the form of a shallow cup, with the print or um
. Studies in fossil botany . Paleobotany. i66 STUDIES IN FOSSIL BOTANY Fig. 67). The characteristic feature of the Ulodendron stem consists in the presence of roundish scars,often of very large size, usually arranged alternately in two vertical rows, one row on each side of the stem. On the larger Ulodendra these scars have a diameter of from 4 to 6 inches. Within the scar, usually somewhat below the centre, is a print or stump, representing either the stalk or the woody cylinder of some lateral appendage. The scar as a whole is depressed, having the form of a shallow cup, with the print or umbili- cus at the bottom (see Fig. 67). The surface of the cup is usually marked with radiat- ing ridges on the part above the umbilicus,while the lower Surface of Part bears spirally arranged. Fig. 67. — Ulodendron. branch, showing two large scars, with prominent DOintS the central print c, and numerous Lepidodendroid leaf-bases. On the right the leaves are seen. Reduced. After Schimper. The large scars are really depressions, but, owing to the shading, appear in the figure as elevations. They can be seen as depressions if the figure is reversed. The nature of these curious objects was long in dispute, and is still by no means cleared up, though specimens have been de- scribed with " cones " still attached to the scars,1 thus 1 D'Arcy Thompson, "Notes on Ulodendron and Halonia" Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Scott, Dukinfield Henry, 1854-1934. London, A. and C. Black
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