. Botany for high schools and colleges. Botany. BBYAGB^. 359. Fig. 247.—Two capsules of Bnjvm argfideunt. The one on the left is still per- fect ; at its apex i-^ shown the lid or operculum; the in some cases a development whicli foreshadows the differentiation of the stem into the epidermal, fibre-vascular, and fandamental systems of the higlier plants. In Polytriclmm, for example, there can be no doubt that the axial and extra-axial bundles of elongated cells with thickened walls found in tlie stem represent tlie fibro-vascular bundles of the Pteridophytes and Phanerogams ; the bundles of el
. Botany for high schools and colleges. Botany. BBYAGB^. 359. Fig. 247.—Two capsules of Bnjvm argfideunt. The one on the left is still per- fect ; at its apex i-^ shown the lid or operculum; the in some cases a development whicli foreshadows the differentiation of the stem into the epidermal, fibre-vascular, and fandamental systems of the higlier plants. In Polytriclmm, for example, there can be no doubt that the axial and extra-axial bundles of elongated cells with thickened walls found in tlie stem represent tlie fibro-vascular bundles of the Pteridophytes and Phanerogams ; the bundles of elongated thin-walled cells which pass downward through the stem from the base of the leaf, in Spladmum, must also be regarded as representing rudimentary foliar bundles. While these higher Mosses cannot properly be classed with vascular plants, their tissues in some cases reach so high a development as to show that there is no abrupt change in pass- ing from the so-called non-vascular plants to the vascular one?. The inflorescence of Bryaceae is hermaphro- dite, monoecious, or dioecious. The sexual or- gans are situated on the apex of the main stem (Acrocarpse), or of short lateral branches its1)'perciSum, exposing'the (Pleurocarpse). The sporogonium, in its de- velopment, carries up the old archegonium as a calyptra, which quickly falls away in some genera {, Bryum, Bartramia, etc.), while in others {, PolytrichuTn, Pogonatum, etc.) it persists as a closely fittins; covering of the capsule ; between these two extremes there are all gradations. The sporogonium is usually long stalked (Fig. 246, B). The capsule ia generally more or less ovoid or cylindrical. It is at first composed of pa- i-cnchymatous tissue, which entirely fills up its interior; as it enlarges, however, an annular in- tercellular air cavity forms, separating a cylin- drical axial portion from the outer portion, which forms the wall of the capsule. The axial cylin- der remains in connection with the re
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1885
