. The structure and development of mosses and ferns (Archegoniatae). Fig. 207.—A, Pinnule of a fertile leaf of Todea (Leptopteris) hymenophylloides, X2;B, fertile pinnule of Osmunda Claytoniana, X3; C-E, three views of the ripesporangium of O, cinnamomea, X40; F, G, sporangia of Todea hymenophylloides,X40; r, annulus. in their formation (Bower (ii); Goebel (17)). Bowersays: In all cases, however, one cell distinctly takes the lead,and this w^e may call the initial cell (Fig. 206, A) ; but thearrangement of its division wall does not, as in the true lepto-sporangiate Ferns, conform to any stric
. The structure and development of mosses and ferns (Archegoniatae). Fig. 207.—A, Pinnule of a fertile leaf of Todea (Leptopteris) hymenophylloides, X2;B, fertile pinnule of Osmunda Claytoniana, X3; C-E, three views of the ripesporangium of O, cinnamomea, X40; F, G, sporangia of Todea hymenophylloides,X40; r, annulus. in their formation (Bower (ii); Goebel (17)). Bowersays: In all cases, however, one cell distinctly takes the lead,and this w^e may call the initial cell (Fig. 206, A) ; but thearrangement of its division wall does not, as in the true lepto-sporangiate Ferns, conform to any strict plan; the initial cellsare oblong, seen in vertical section, and the first divisions arelongitudinal, so as to meet the basal wall: both in the segmentthus cut off and in the central cell, periclinal or sometimesoblique divisions may take place, so that a considerable bulk of 366 MOSSES AND FERNS CHAP. tissue is formed, in the projecting apex of which a single largecell occupies a central position. As in Botrychium the arche-sporium is derived from a single hy
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Keywords: ., bookauthorcampbelldouglashought, bookcentury1900, bookdecade1910
