. Fossil plants : for students of botany and geology . Paleobotany. XLvni] PITYITES 375 Geological Survey I have been able to examine the sections in the Jermyn Street Museum. Graf Solms-Laubach describes the leaves as oval in section, the upper face strongly convex and the lower almost flat as in two-needled Pines, but as shown in fig. 774, A the leaves may be approximately cyhndrical (I mm. in diameter), Uke those of Pimis monophylla or the leaves of Cedrus. There is a single vein accompanied by some radially disposed transfusion-tracheids, the whole being enclosed in a single layer of rathe
. Fossil plants : for students of botany and geology . Paleobotany. XLvni] PITYITES 375 Geological Survey I have been able to examine the sections in the Jermyn Street Museum. Graf Solms-Laubach describes the leaves as oval in section, the upper face strongly convex and the lower almost flat as in two-needled Pines, but as shown in fig. 774, A the leaves may be approximately cyhndrical (I mm. in diameter), Uke those of Pimis monophylla or the leaves of Cedrus. There is a single vein accompanied by some radially disposed transfusion-tracheids, the whole being enclosed in a single layer of rather thick-walled. Fig. 773. Pityites Solmsi. (British Museum, V. 2146; nat. size.) cells. There is no distinct division of the bundle into two halves but there are indications of the presence of a broad median medul- lary ray. The mesophyll-cells have prominent infoldings precisely as in recent Pines, Cedrus, and some other Abietineae (fig. 774, B; cf. fig. 694): the epidermis has a thick cuticle and below it are 1—2 layers of small thick-walled elements. Solms-Laubach speaks of two resin-canals, one at each side of the lamina, but I was unable to distinguish any undoubted canals in the leaf shown in fig. 774. The occasional absence of canals in Abietineous leaves normally. 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 Seward, A. C. (Albert Charles), 1863-1941. Cambridge : University Press
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishercambr, bookyear1898
