. An introduction to the structure and reproduction of plants. Plant anatomy; Plants. 272 LEAFY LIVERWORTS rather drier situations than do the simple thalloid forms ; the leaves, unlike those of Mosses, are usually lobed (Fig, 147, A), and sometimes even deeply divided. Some of the commonest of the foliose Liverworts belong to the genera Lophocolea and Cephalozia, whose structure is typical of these forms. Here there is a prostrate stem, bearing on either flank a row of over- lapping, sessile, two-lobed leaves (Fig. 147, A) and, on the underside, a few small scales with tufts of rhizoids arisi
. An introduction to the structure and reproduction of plants. Plant anatomy; Plants. 272 LEAFY LIVERWORTS rather drier situations than do the simple thalloid forms ; the leaves, unlike those of Mosses, are usually lobed (Fig, 147, A), and sometimes even deeply divided. Some of the commonest of the foliose Liverworts belong to the genera Lophocolea and Cephalozia, whose structure is typical of these forms. Here there is a prostrate stem, bearing on either flank a row of over- lapping, sessile, two-lobed leaves (Fig. 147, A) and, on the underside, a few small scales with tufts of rhizoids arising from their base. The two lobes of the leaves are often folded to- gether. In some of the foliose forms the leaves are complicated by the modifica- tion of the lower lobe into a water- receptacle. Frul- lania, a common epiphyte on tree- trunks, affords an extreme ex- ample, in which this lobe is de- veloped as a smah, helmet-shaped pitcher (Fig. 148). In the leafy Liverworts the growing point of the stem is invariably a single cell. The thallus of most Liverworts exhibits little anatomical differentiation. In such an one as Pcilia, for example, all the cells, apart from their elongated form in the region of the midrib, are similar in shape, and most of them contain the numerous smell discoid chloroplasts which are typical of Bryophyta. Fig. 148.—Photomicrograph of a small portion of the epiphytic Liverwort FruUania tamarisciiii, show- ing the pitcher-like lower lobes of the leaves. [Photo, E. J. S.]. 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 Fritsch, Felix Eugene, 1879-; Salisbury, E. J. (Edward James), Sir, b. 1886. London, G. Bell and sons ltd.
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectpl, booksubjectplants
