206 BOTANY. 



of smaller ones. Look for the rapid movement of protoplasm which 

 is so marked in these plants. 



(c) Mount several spore-fruits in various stages of development. 

 Note the covering layer of spirally coiled cells surrounding the car- 

 pogone (in young specimens) or the spore (in older specimens). 



(d) Mount several full-grown antherids. Carefully crush them 

 and look for antherozoids, which are produced in chains of cells. 



Systematic Literature. — Allen, Characese of America, 1, 3. 

 Flora of Nebraska, 2 : 122-128. pi. S5-36. 



