. Comparative anatomy of the vegetative organs of the phanerogams and ferns;. Plant anatomy; Ferns. FIG. 154.âPotamogeton crispus (40). End of a shoot. Longitudinal section parallel to the median planes of the two rows of leaves, cleared by potash. The successive leaves nuinbered r, 2â10; â vi, V2 the sheaths of the corre- sponding leaves; the sheaths of the upper leaves were obscured in the pro- cess of preparation, and are partly omitted in the drawing. The median vascular bundles of leaves 9 and 10 are just beginning to develope; the seven highest leaves are still without bundles. Fig. 125.
. Comparative anatomy of the vegetative organs of the phanerogams and ferns;. Plant anatomy; Ferns. FIG. 154.âPotamogeton crispus (40). End of a shoot. Longitudinal section parallel to the median planes of the two rows of leaves, cleared by potash. The successive leaves nuinbered r, 2â10; â vi, V2 the sheaths of the corre- sponding leaves; the sheaths of the upper leaves were obscured in the pro- cess of preparation, and are partly omitted in the drawing. The median vascular bundles of leaves 9 and 10 are just beginning to develope; the seven highest leaves are still without bundles. Fig. 125.âPotamogeton crispus (40). End of a shoot Thick "median longitudinal section perpendicular to the median plane of both rows of leaves, cleaved by potash; the sheaths were obscured by the process of preparation, and are omitted in the drawing. The successive leaves are numbered in order. The series of unevenly numbered leaves are uppermost, nearest the observer; the even numbers are below. The same is the case with the median bundles, whicH go to the respective series and unite in the axile bundle 7>i, The median bundle is plainly seen as far as the sixth leaf from the apex ; the lateral bundles united to form the two bundles i, I, beginning at the eleventh leaf from the apex (g) in the node; the development of 4 and 5 is not yet completed downwards through the intemode. In the intemodes the air-cavities are first formed from below upwards, and from the outside mwards. In each of the sheathuig leaves, which alternate in two rows, the bundles pass out at the node. The median bundles run down through the internodes in the manner described for P. lucens and gramineus (Fig, 124). The lateral ones (Fig. -125) pass on each side almost perpendicularly from a bundle which traverses the stem perpendicularly, and corresponds exactly in position-and relatively late* appear- ance to the cauline bundles of the' other species, so that the arrangement of the. Please note that these
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Keywords: ., bookcentury1800, bookdecad, booksubjectplantanatomy, bookyear1884
