THE GREAT GROUPS OF BEYOPHYTES 



313 



The air chambers are outlined on the surface as small 



rhombic areas (areola), each containing a single air pore. 



Peculiar reproductive bodies are also developed upon 



the dorsal surface of Marcliantia for vegetative multiplica- 



Fig. 287. Marchantia polymorpha : 1, partial section through archegonial disk, show- 

 ing archegonia with long necks, and venters containing eggs; 9, young archego- 

 nium showing axial row; 10, superficial view at later stage; 11, mature archego- 

 nium, with axial row disorganized and leaving an open passage to the large egg; 

 12, cross-section of venter; 13, cross-section of neck.— After Knt. 



tion. Little cups (cupules) appear, and in them are numer- 

 ous short-stalked bodies (gemma), which are round and 

 flat (biscuit-shaped) and many-celled (Figs. 284, 285). The 



