. Fossil plants : for students of botany and geology . Paleobotany. 140 THALLOPHYTA. [CH. records how a captain of a brig employed his crew for two bitterly cold days in collecting Lessonia stems which had been washed up on the beach, thinking bhey were trunks of trees fit for burning. On our own coasts we are familiar with the common Laminaria, the large bro^vn seaweed with long and strap-shaped or digitate fronds which grows on the rocks below low-tide level. The frond passes downwards into a thick and tough stipe firmly attached to the ground by. special holdfasts. A transverse section of t
. Fossil plants : for students of botany and geology . Paleobotany. 140 THALLOPHYTA. [CH. records how a captain of a brig employed his crew for two bitterly cold days in collecting Lessonia stems which had been washed up on the beach, thinking bhey were trunks of trees fit for burning. On our own coasts we are familiar with the common Laminaria, the large bro^vn seaweed with long and strap-shaped or digitate fronds which grows on the rocks below low-tide level. The frond passes downwards into a thick and tough stipe firmly attached to the ground by. special holdfasts. A transverse section of the stalk of a fairly old plant presents an appearance not unlike that of a section of a woody plant. In the centre there is a well-defined axial region or pith consisting of thick walled, long and narrow tubes pursuing a generally vertical though irregular course, and embedded in a matrix of gelatinous substance derived from the mucilaginous degeneration of the outer portions of the cell-walls. The greater part of such a section consists, however, of regularly disposed. Fig. 29. A, Transverse section of the stipe of a Laminaria, slightly enlarged. B, A small piece of the tissue between the central 'pith' and 'cortex' showing the radially disposed secondary elements more highly magnified. rows of cells which have obviously been formed by the. 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
