CODIUM, ETC. 81 



If the material be suitable, the sexual organs (gametangia) 

 are to be found as 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 recognised on 

 different individuals. 



Observations may also be made on specimens of the native 

 genus Bryopsis. 



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. 



Acetabularia, which is a native of southern seas, and Botrydium, 

 which is to be found growing on moist soil in swampy places, 

 may also be examined with advantage if material can be 

 obtained. 



