. The structure and development of mosses and ferns (Archegoniatae). the germinating spore divides by a transverse wall into two equal cells, one of which continues to grow and divide8 114 MOSSES AMD FERNS CHAP. until a short filament is formed. After a varying number oftransverse divisions an oblique wall is formed in the terminalcell, and a second one nearly at right angles to it. By thesedivisions the dorsiventral character is established, the first-formed segment being ventral. A third oblique wall nowarises, intersecting both of the others, and the three include atetrahedral cell which is
. The structure and development of mosses and ferns (Archegoniatae). the germinating spore divides by a transverse wall into two equal cells, one of which continues to grow and divide8 114 MOSSES AMD FERNS CHAP. until a short filament is formed. After a varying number oftransverse divisions an oblique wall is formed in the terminalcell, and a second one nearly at right angles to it. By thesedivisions the dorsiventral character is established, the first-formed segment being ventral. A third oblique wall nowarises, intersecting both of the others, and the three include atetrahedral cell which is the permanent apical cell of the youngplant. The ventral segments do not at first form any trace ofleaf-like structures, and in the dorsal segments the leaves are atfirst simple rows of cells; but a little later the leaves showplainly their two-lobed character, each being made up of tworows of cells united at the base. From the ventral segmentsthe amphigastria develop gradually, being quite absent in theearlier ones. Chiloscyphus closely resembles Lophocolea, but.
Size: 1594px × 1567px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorcampbelldouglashought, bookcentury1900, bookdecade1910
