340 



GENERAL MORPHOLOGY OF PLANTS 



the egg cases hang downward from the underside of the gamete 

 bearer, the capsule also grows downward. At first the venter of the 



Fig. 300. 



Marchantia pplymorpha, archegonium at the right with egg; archegonium at the left with 

 young spprogonium; />, curtain which hangs down around the archegonia; e, egg; v, venter of 

 archegonium; n, neck of archegonium; sp, young sporogonium. 



egg case increases in size to form a hood (calyptra) which protects 

 the young egg case. The hood is later broken. At maturity the 



Fig. 301. 



One is open, 

 The junction 



of the stalk of the sporogonium with the receptacle is the point of attachment of the sporophyte 



of Marchantia with the gametophyte. 



Section of archegonial receptacle of Marchantia polymorpha; ripe sporogonia. 

 scattering spores and elaters; two are still enclosed in the wall of the archegonium. 



stalk of the capsule elongates and pushes the capsule out 

 from between the delicate tissue membranes which protected 



