MARCHANTIA POLYMORPHA. 91 



location. The oospore is first divided by the basal 

 wall into two regions, one of which develops the foot 

 of the sporophyte, and the other develops the capsule. 

 The wall layer of this capsule is sterile, and within this 

 the spores are produced. Distributed about among the 

 spores are elaters, specialized structures that move the 

 spores about and usually hold several of them together. 

 It will be noted also that the sporophyte of this plant has 

 relatively more sterile tissues than has the sporophyte of 

 Riccia, there being in addition to the sterile walls and 

 elaters, the foot and stalk, which place the spores in 

 a position more favorable for distribution. 



