Fig. 4 shows the male and female organs very much magnified. The antheridium. A, is a stalked, club-shaped structure, inclosing a large number of sperm-cells, b, each of which produces a spiral spermatozoid, c. These minute bodies move rapidly by means of two cilia, and find their way to the neck of the female organ, B. The germ-cell, b, to be fertilized, is at the base of the long structure, with a mucilaginous channel. h, leading down to it. After the spermatozoids have united with the germ-cell, the latter soon begins a new growth, and a young sporangium results. Fig. 5 shows different stages in the development of the sperm-case; and in Fig. 6 is seen a vertical section of one fully grown, showing the various parts of theca, calyptera, operculum, etc. In this complicated sporangium, small spores in great numbers are produced, and with their perfection ends the last chapter in the life-history of the moss.