. Botany for high schools and colleges. Botany. 354 BOTANY. below, where there are two layers. The neck of the arche- gonium at first contains an axial row of cells, but these into a just before become dissolved and transformed h. Fi^. 243.—Development of the siTorogonium of Fimaria hygrometrica. A, longitudinal gec- tion of tlie archegonium, 5, 6, shortly after fer- tilization ; h, neck ; /, apical portion of young sporogonium ; f, basal portion of young sporo- gonium. B, vertical section of a femalelflower; t\ young sporogonium elongating, and carrying up the remains of the old archegonium,
. Botany for high schools and colleges. Botany. 354 BOTANY. below, where there are two layers. The neck of the arche- gonium at first contains an axial row of cells, but these into a just before become dissolved and transformed h. Fi^. 243.—Development of the siTorogonium of Fimaria hygrometrica. A, longitudinal gec- tion of tlie archegonium, 5, 6, shortly after fer- tilization ; h, neck ; /, apical portion of young sporogonium ; f, basal portion of young sporo- gonium. B, vertical section of a femalelflower; t\ young sporogonium elongating, and carrying up the remains of the old archegonium, c (ncjw called the calyptra) ; A, neck of old archego- nium. C, a later stage of the same. In B and C the sporogonia are seen to be growing down- ward into the tissues of the leafy stem A X 500; 5 and C much less.—After Sachs. mucilaginous mass the time of fertilization. The germ- cell lies in the lower swollen portion of the ar- chegonium ; it consists of a naked rounded mass of protoplasm. At the time of fertilization the upper- most cells of the neck of the archegonium diverge from one another, and thus form an open chan- nel to the germ-cell. 463.—Fertilization takes place in the water, or in the presence of a considerable amount of moisture. The spermato- zoids, which are j)roduced in great i^umbers, move through the water by means of their vibratile cilia, and some of them find their way down the channels of the archego- nia, where they unite their substance with the germ- cells. As a result of this union, the germ-cell sur- rounds itself with a wall of cellulose, and soon un- dergoes division in various directions, giving rise to a many-celled mass, the young sporogonium (/, /', Fig. 243, A). In most Mosses the young sporogonium elongates rap- idly, and while its upper end carries up the remains oi. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustra
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