The structure & development of the mosses and ferns (Archegoniatae) . Fig. go.—Funaria hygrometrica (Sibth.). Development of the antheridium. A-D, Longitudinalsections of young stages, X 600; D is cut in a plane at right angles to C ; E, optical section ofan older stage, X300; G, F, cross-sections of young antheridia, x6oo; H, diagram showing thefirst divisions in the antheridium ; I, young spermatozoids, X 1200. wall. The outer cell either becomes at once the mother cell ofthe antheridium, or other transverse walls may occur, so that ashort pedicel is first formed (Fig. 90, A). Finally in the
The structure & development of the mosses and ferns (Archegoniatae) . Fig. go.—Funaria hygrometrica (Sibth.). Development of the antheridium. A-D, Longitudinalsections of young stages, X 600; D is cut in a plane at right angles to C ; E, optical section ofan older stage, X300; G, F, cross-sections of young antheridia, x6oo; H, diagram showing thefirst divisions in the antheridium ; I, young spermatozoids, X 1200. wall. The outer cell either becomes at once the mother cell ofthe antheridium, or other transverse walls may occur, so that ashort pedicel is first formed (Fig. 90, A). Finally in theterminal cell, as in Andre£Ea^.:\.vjo intersecting walls are formedenclosing a two-sided apical cell, from which two ranks ofsegments are cut off in regular succession (Figs. A, B, C). Thenumber of these segments is limited, in Fuiiaiia not oftenexceeding seven, and after the full number has been formed, the vir THE BRYINEAL 189 apical cell is divided by a septum parallel with its outer faceinto an inner cell, which with the inner cells of the segmentsforms the
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Keywords: ., bookcentury1800, bookdecade1890, bookidstructuredev, bookyear1895
