. Carnegie Institution of Washington publication. THE GAMETOPHYTE 23 this projection is less marked, although this may be somewhat decided in the ripe antheridium. The first division in the inner cell is usually vertical, but may be transverse, at least in O. pendulum (fig. 13, A). The second walls intersect the first at right angles, and there are always four nearly equal inner cells resulting (fig. 13, D). The third set of walls is vertical, and the next, in some cases at least., is in the same direction. This is not true, however, of the deeper and narrower type of antheridium. Further divi
. Carnegie Institution of Washington publication. THE GAMETOPHYTE 23 this projection is less marked, although this may be somewhat decided in the ripe antheridium. The first division in the inner cell is usually vertical, but may be transverse, at least in O. pendulum (fig. 13, A). The second walls intersect the first at right angles, and there are always four nearly equal inner cells resulting (fig. 13, D). The third set of walls is vertical, and the next, in some cases at least., is in the same direction. This is not true, however, of the deeper and narrower type of antheridium. Further divisions occur until the number of spermatocytes is very large. The fully developed mass of spermatocytes is plainly visible to the naked eye, and in O. pendulum may reach a diameter of more than 325 p. 250 cells and upward may be counted in a single section of a large antheridium, and this would mean that there are several thousand in the whole antheridium—perhaps more than in any other Pteridophyte. In O. moluccanum (fig. 12), the number of spermatocytes is much smaller, while in this regard the antheridium of 0. vulgatum appears to be intermediate between that of 0. moluccanum and 0. JUG. 12.—Op/no^loaum molurcamtm. A. Ripe antheridium. X180. B, C. Young antheridia. X320. D. Surface view of antheridium, showing opercular cell. The nuclei of the young cells show a conspicuous nucleolus, which becomes less marked in the later stages of the antheridium. According to Mettenius, the outer wall of the antheridium in 0. pedunculosum is composed of two layers of cells; but both Lang and Bruchmann found that the central part of this outer wall of the. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Carnegie Institution of Washington. Washington, Carnegie Institution of Washington
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