. Fossil plants : for students of botany and geology . Paleobotany. XXIIl] PSARONIUS 419 different degrees of looping of other bands represent stages in the giving off of leaf-traces which eventually pass out as V-shaped meristeles. Beyond the leaf-traces and scleren- chymatous bands the section consists of transverse sections of adventitious roots. The surface-features of Psaronius infarctus are probably represented, as Zeiller points out, by the cast described by Lesquereux as Caulopteris peltigera (fig. 298, A).. Fig. 297. Pecopteris Sterzeli: a, pinnule. (After Eenault and Zeiller. yV iiat
. Fossil plants : for students of botany and geology . Paleobotany. XXIIl] PSARONIUS 419 different degrees of looping of other bands represent stages in the giving off of leaf-traces which eventually pass out as V-shaped meristeles. Beyond the leaf-traces and scleren- chymatous bands the section consists of transverse sections of adventitious roots. The surface-features of Psaronius infarctus are probably represented, as Zeiller points out, by the cast described by Lesquereux as Caulopteris peltigera (fig. 298, A).. Fig. 297. Pecopteris Sterzeli: a, pinnule. (After Eenault and Zeiller. yV iiat- size.) The Psaronius shown in fig. 297 is one of the few examples illustrating the connexion between fronds and stem. The leaf (Pecopteris Sterzeli Zeill. and Ren.^) is quadripinnate and is described as reaching a length of at least 3 metres; the ultimate segments are entire or lobed. The stem is charac- terised by elliptical scars, 6—8 cm. x 3'.5—4 cm., with leaf- traces like those in Caulopteris peltigera. The fronds of Pecopteris Pluckeneti, a Pteridosperm, bear a very close 1 Benault and Zeiller (88) A. Pla. v.— 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
