Nature and development of plants . at base with spirally arranged leaves, has elongated,lifting the mature sporophyte into the air. The enlargement of the stem,b, is due to the growth of the foot region of the sporophyte; ca, remainsof the ruptured archegonium or calyptra; 0, lid or operculum of the cap-sule.—After Schimper. The stomata and chlorenchyma which were so conspicuous inAnthoceros are less perfectly represented, but the spore mothercells are still developed in a dome-shaped zone. This ratherminute sporophyte at maturity barely breaks through the arche-gonium, known in this condition
Nature and development of plants . at base with spirally arranged leaves, has elongated,lifting the mature sporophyte into the air. The enlargement of the stem,b, is due to the growth of the foot region of the sporophyte; ca, remainsof the ruptured archegonium or calyptra; 0, lid or operculum of the cap-sule.—After Schimper. The stomata and chlorenchyma which were so conspicuous inAnthoceros are less perfectly represented, but the spore mothercells are still developed in a dome-shaped zone. This ratherminute sporophyte at maturity barely breaks through the arche-gonium, known in this condition as the calyptra, which coversthe capsule as a cap. The absence of a conspicuous stalk or setain the sporophyte of Sphagnum is provided for by the elongationof the upper part of the moss stem which pushes the sporophyte 272 THE HIGHER MOSSES above the leaves and exposes the capsule to the winds quite aseffectually as the seta of the hepatics and mosses (Fig. 203, 5).The spores are freed by the falling off of a circular lid, or,. Fig. 204. Fig. 205. Fig. 204. Germination of the spore of Sphagnum: A, early growth ofthe spore. B, later development—sp, spore; b, bud developing into mossplant. C, margin of the thallus, showing the origin of the bud.—AfterCampbell. Fig. 205. The twisted stalk moss, Funaria: A, two sporophyte-bearingplants, the remains of the archegonium or calyptra still attached to thecapsule on the right. B, enlarged view of plant with the young sporo-phyte, still enclosed in the archegonium, just emerging above the , the male plant bearing the antheridia in a conspicuous rosette of , upper portion of the sporophyte. showing the twisting of the stalk orseta that assist in sifting the spores through the teeth, peristome, thatencircle the mouth of the capsule. operculum, as is the case among the majority of the mosses( Fig. 203. o). This is effected by a ring of thin-walled cells,the annulus, that lie in the groove just below the operculum andwh
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