436 PRACTICAL BOTANY 



are to be found in the form of short cysts, borne as lateral branches 

 among the radiating peripheral sacs of the thallus, and completely 

 overtopped by them. According to their size, smaller male 

 (antheridia) and larger female (oogonia) are to be recognized 

 on different individuals. 



Observations may also be made on specimens of the native 

 genus Bryopsis, which is to be met with occasionally on rocky 

 shores. 



If specimens be at hand, comparison should also be made of 

 various species of Caulerpa, in which the thallus attains high 

 complexity and varied conformation, though it is not partitioned 

 into cells : in this genus reproductive organs have not yet been 

 observed. 



Acetalularia, which is a native of southern seas, and Bolrydium, 

 w.hich is to be found growing on moist soil in swampy places, 

 may also be examined with advantage if material can be 

 obtained. 



