Mosses and Lichens 



which divides to form a stem or pedicel, while the second divides 

 to form the globular part of the antheridium. The mature 

 antheridium bursts at the apex, the margins roll back and a cloud 



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Sphagnum acutifolium. 

 Male flower-cluster with 

 sterile branch at base. 



Moss plant on protonema of Sphagnum acutifolium. 



of flattened membranous sacs (vesicles), each containing one 

 spirally coiled antherosoid, are thrown out. The antherosoids 

 are soon set free by the breaking down of the vesicle wall. 

 Each antherosoid is a spirally coiled cell, club-shaped, with two 



vibratile lashes at the 

 attenuated end. 



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Sphagnum 

 subsecundum. 

 Young arche- 

 gonium. 



Sphagnum 

 papillosum. 

 Vertical sec- 

 tion of a de- 

 v e 1 o p i n g 

 archegonium. 



Sphagnum cuspidatum. Vertical 

 section to show young embryo. 



Sphagnum cuspida- 

 tum. Vertical section 

 of a ripe archegonium 

 to show egg-cell. 



Archegonium. The archegonium is developed by cell-division; 

 it is similar to a tiny flask, at the base of which is an egg-cell 

 (ovum) which, after fertilisation, is to become a spore-case (i, 2, 3). 



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