64 BEITISH MOSSES. 



ences will be apparent from the figures. The sporangium, 

 as in the Mosses, takes its rise from an archegone. In 

 the Mosses this organ is concealed in modified leaves, and 

 is generally speaking not easy to detect. In these Junger- 

 manniaceas the archegones form conspicuous green organs 

 (ar) hi which, in the earlier stages, the dark-coloured 

 sporangia appear to rest (Fig. 36, s). They are subse- 

 quently raised on a seta or stalk, generally of a perfectly 

 white cellular structure. The sporangium is not divided 

 into capsule and lid, but opens as shown in Fig. 87, by the 

 springing backward of the four leaves which constitute it, 

 and emits large quantities of spores (sp), interspersed with 

 very curious structures , known as elaters (el) . These elaters , 

 with some attached spores, are seen more highly magni- 

 fied in Fig. 88. The elaters are endless threads, twisted 



...el 



FIG. 38. Spores and elaters of Jungermarmia 

 magnified, sp, spores ; el, elaters. After nature. 

 I.P. 



into spirals, and when liberated the spirals rapidly twist 

 and twirl about, and in so doing, aid in dispersing the 



