MARCHANTIA POLYMORPHA. 89 



b. The archegonia, which in such material usually appear 

 in various stages of development. With a fully formed 

 archegonium locate the following parts: 



i. The elongated basal region, the stalk. 

 ii. The swollen region, the venter. 

 iii. The elongated region, the neck. 

 iv. Within the venter, the egg. Frequently it will be 

 seen that the egg has been fertilized and has already 

 begun to germinate. 

 v. Within the neck, the neck canal cells. 

 vi. The cell between the neck canal cells and the egg, 

 the ventral canal cell. 



c. Arising from the region near the base of the archegonium, 

 an outgrowth, the perianth, which later develops about 

 the archegonium. 



d. Draw a fully formed archegonium. 



e. Draw stages in the development of an archegonium. 



/. Note the changes in the size and form of the archegonial 

 heads as they mature. 



IV. THE SPOROPHYTE AND ASEXUAL REPRODUCTION. 



Make sections of an archegonial head that is more mature 

 and study the changes that occur in the germination and 

 development of the oospore. Observe: 



1. The first division of the oospore by the basal wall. 



2. Trace the changes in form of the body and the increase 



in the number of cells until the number can no longer be 

 determined. 



3. Draw. 



From old heads dissect out the fully formed sporophytes 

 enveloped by the perianth, and observe: 



4. The three distinct regions, foot, stalk, and capsule. 

 Draw. 



5. The spores. 



