. Studies in fossil botany . Paleobotany. CORDAITEAE 549 not enter the nucellus, a course which resembles that in the seeds of recent Cycads, as interpreted by many observers. In other respects the seed agrees with Cordaicarpus. Two archegonia (ar), spherical in form, are clearly shown ; between them, the endosperm has an upward prolongation, which is interesting, as it exactly corresponds to the structure found in Ginkgo at the present day, and compared by Hirase to a TTU ar. nu. ar Fit;. 198.—Cycartitiocarpus emgustodunensis. Upper part of seed, in longitudinal section, int, integument; mi,
. Studies in fossil botany . Paleobotany. CORDAITEAE 549 not enter the nucellus, a course which resembles that in the seeds of recent Cycads, as interpreted by many observers. In other respects the seed agrees with Cordaicarpus. Two archegonia (ar), spherical in form, are clearly shown ; between them, the endosperm has an upward prolongation, which is interesting, as it exactly corresponds to the structure found in Ginkgo at the present day, and compared by Hirase to a TTU ar. nu. ar Fit;. 198.—Cycartitiocarpus emgustodunensis. Upper part of seed, in longitudinal section, int, integument; mi, micropyle; nil, remains of nucellus; , pollen-chamber, containing pollen-grains ; the chamber has a long neck or canal, extending up into the micropyle ; fir, endosperm ; ar, archegonia, -Magnified. After Renault. tent-pole, supporting the nucellar membrane, which represents the tent. The pollen-chamber (pc), with its long neck rising up into the micropyle (mi; cf. Figs. 196 and 197), contains pollen-grains. Only the sclerotesta (int) of the seed is shown in the figure. Although so many Pteridospermous and Gymno- spermous seeds have been discovered in the Carboni- ferous formation, and often in a wonderful state of. 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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