The structure & development of the mosses and ferns (Archegoniatae) . B. ;/-Mi ^^. Fig. 205.—AzoUa filiculoidcs (Lam.). A, Mature sporophyte, X2; B, lower surface of a branchwith two microsporangial sori (sp), x6 ; C, macrosporangial (w«) and microsporangial (ini)sori, X 10. become absorbed, as Strasburger ^ states, but remains intact,though very much compressed, until the spore is ripe. ? Strasburger (6), p. 71. 398 MOSSES AND FERNS chap. In the microsporic sorus, the apex of the placenta does notdevelop sporangia, but remains as a sort of columella (Fig. 202, A). The sporocarps of Salvinia a
The structure & development of the mosses and ferns (Archegoniatae) . B. ;/-Mi ^^. Fig. 205.—AzoUa filiculoidcs (Lam.). A, Mature sporophyte, X2; B, lower surface of a branchwith two microsporangial sori (sp), x6 ; C, macrosporangial (w«) and microsporangial (ini)sori, X 10. become absorbed, as Strasburger ^ states, but remains intact,though very much compressed, until the spore is ripe. ? Strasburger (6), p. 71. 398 MOSSES AND FERNS chap. In the microsporic sorus, the apex of the placenta does notdevelop sporangia, but remains as a sort of columella (Fig. 202, A). The sporocarps of Salvinia are like those of Azolla, but thetwo layers of cells are separated by a series of longitudinal air-spaces which correspond to ridges upon the surface of the sporo-carp (Fig. 196, D). The microsporangia of Azolla have a long stalk, whichis composed of usually two, but sometimes three rows ofcells. The sixteen sporogenous cells all develop, so thatthere are normally sixty-four microspores in each have the exospore thin and smooth, and are included i
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Keywords: ., bookcentury1800, bookdecade1890, bookidstructuredev, bookyear1895
