iS 



HANDBOOK OF MOSSES. 



downward pressure on the delicate tissues of the arche- 

 gonium causes it to rupture near the base ; the upper part 

 being carried upwards by the growing sporogonium (fig. 8, 

 B <r), forms the hood or calyptra, the lower part is left sur- 



FIG. 8. A , origin of the sporogonium. ff in the ventral portion of the arche- 

 gonium (longitudinal section x 500). B, C.different further stages of development of 

 the sporogonium,./; and of the calyptra, c ; h, neck of the archegonium ( x about 40). 



rounding the base of the sporogonium and forming a sheath, 

 which is called the vaginula (Lat, a little sheath). At the 

 top of the sporogonium the capsule is formed, within whicl: 

 the spores are developed. 



