. Fossil plants : for students of botany and geology . Paleobotany. XXXII] CALAMOPITYS 191 family-name Calamopityeae and recognised a close anatomical affinity between Calamofitys and Lygino'pteris, a conclusion which led to the incorporation of Unger's genus in the Pteridosperms. Further data have been suppUed by Zalessky"- and, more recently, by Scott and Jeffrey^ who have recognised Calamopitys in Lower Carboniferous beds in Kentucky. Calamofitys Saturni Unger. Our knowledge of this and other species is confined to stems and petioles. One of the largest examples of the species is a pie
. Fossil plants : for students of botany and geology . Paleobotany. XXXII] CALAMOPITYS 191 family-name Calamopityeae and recognised a close anatomical affinity between Calamofitys and Lygino'pteris, a conclusion which led to the incorporation of Unger's genus in the Pteridosperms. Further data have been suppUed by Zalessky"- and, more recently, by Scott and Jeffrey^ who have recognised Calamopitys in Lower Carboniferous beds in Kentucky. Calamofitys Saturni Unger. Our knowledge of this and other species is confined to stems and petioles. One of the largest examples of the species is a piece of stem-with a diameter of 1-5 cm.: the single stele consists of a parenchymatous pith enclosed by secondary xylem made up of tracheids with 4—8 rows of bordered pits and medullary. Via. 454. Calamopiiys Saturni. B, stem with leaf-base; x, primary xylem and pith; black patches represent leaf-traces; C, stem with two leaf-bases; D, section of petiole. (After Solms-Laubaoh.) rays more than one cell broad and of considerable depth. Between the inner edge of the wood and the pith are groups of primary xylem (fig. 454, B, x) which, hke those in Lyginofteris, constitute the leaf-traces: each has a single internal protoxylem strand (fig. 455, B). The comparatively wide cortex consists of paren- chyma with a hypoderm of the Sparganum type. Bach primary xylem-strand passes out as a single leaf-trace through the secondary xylem and on emerging divides into two as in Lyginofteris: these branch in the cortex and the two are replaced by six in the leaf-base (fig. 454, B—D). As seen in figs. 454, C, 455, A, the boundary between the stem proper and the decurrent leaf-base is marked by a line of stereome strands. The petioles of Calamo- 1 Zalessky (11). ^ Soott and Jeffrey (14).. 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 origi
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishercambr, bookyear1898
