BRYOPHYTA. 



149 



idia. The archegonium is flask-shaped, in the bottom of 

 which is a naked mass of protoplasm, the germ-cell, which 

 is the essential part of the female organ. The antheridium 

 is generally club-shaped, or sub-spherical, supported by a 

 pedicel, and filled with many sperm-cells, each of which 

 contains a single, spirally-coiled spermatozoid. The neck 

 of the archegonium is open at the time of fertilization, 

 and into it pass the free spermatozoids, which fuse with 

 the germ-cell. Thereupon a thick wall, or covering, is 



formed, and cell-division in the germ-cell takes place. 

 This, the spore-case (sporangium), supported by a pedicel, 

 or seta, is nourished by the plant in which it is formed, 

 but yet has no organic connection with it ; and is, therefore, 

 called the second, or non-sexual generation. Within the 

 sporangium the spores are formed, and contain, besides 

 colorless protoplasm, starch and drops of oil, also chloro- 

 phyll grains. When ripe, the spore-case (as, for example, 

 in Hypnurn) opens by a more or less beaked lid, called 

 the operculum (Fig. 262, op), which, in many species, is 



Fig. 262. A Moss ; Dicranum glaucum ; op, operculum ; cal, calyptra ; pir, 

 peristome; j;^^ sporangium; J^ seta : J/*, spores. 



