. Text-book of botany, morphological and physiological. Botany. Fig. 23.—Pt'nus sylvestris; radial longitudinal sec- tion through the wood of a rapidly growing branch; cb cambial wood-cells; a—e older wood-cells ; t tf t" bordered pits of the wood-cells, enlarging with age; st large pits where cells of the medullary rays touch the wood-cells (X 55°)-. FIG. 24.—Pz'nus sylvestris; A transverse section of mature wood-cells (X 800); m middle lamella of the common partition; i inner layer, clothing the cavity; z intermediate layer of the cell- wall ; / a mature pit cut through the middle ; t'
. Text-book of botany, morphological and physiological. Botany. Fig. 23.—Pt'nus sylvestris; radial longitudinal sec- tion through the wood of a rapidly growing branch; cb cambial wood-cells; a—e older wood-cells ; t tf t" bordered pits of the wood-cells, enlarging with age; st large pits where cells of the medullary rays touch the wood-cells (X 55°)-. FIG. 24.—Pz'nus sylvestris; A transverse section of mature wood-cells (X 800); m middle lamella of the common partition; i inner layer, clothing the cavity; z intermediate layer of the cell- wall ; / a mature pit cut through the middle ; t' the same, but at a thicker part of the section, the part of the cavity of the pit lying be- neath is seen in perspective; t" a pit cut through beneath its inner opening; B transverse section through the cambium (X 800); c cambium; h wood-cells still young; between them two very young wood-cells with pits ^beginning to form; (C—Fdiagrammatic). walls of scalariform vessels, which are developed with peculiar beauty in the higher Cryptogams, the bordered pits are fissure-like; they often stretch across the partition-wall of two adjoining cells, but are very narrow in the longitudinal direction. In Fig. 27, A, is shown the lower half of a vessel of this kind with fissure- like pits, separated by thickening-masses like rungs of a ladder; the larger white spaces wood of Robinia pseudacacia, &c. [See Journ. of Bot. 1872, pp. 321-323* *• I26i and Reess, Bot. Zeitg. 1868, pp. 1-11, t. 1 ; also infra, Book iii. Sect. 16.]. 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 Sachs, Julius, 1832-1897; Vines, Sydney Howard, 1849-1934. ed. and tr. Oxford, Clarendon press
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1882
