12 



only in veiy old septa that we were unable to demon- 

 strate the presence of staiiiable substance in the channel. 

 Finally the lumen becomes completely obliterated. 



B. Eeproductive Organs. 



The reproductive organs of Codium have been the 

 subject of investigation by several algologists. 



Thuret (Eecherches sur les zoospores des Algues, Ann. 

 Sc. Nat., 3e. Ser., Bot. XIY.) showed that oval sporangia 

 were formed from tlie upper parts of the swollen palisade 

 "cells," each giving rise to biciHate swarmspores which, 

 he affirmed, developed directly into new basal filaments. 



Derbes and Sober (Memoire sur quelques points de la 

 physiologie des Algues, Suppl. des Comp. Eenl., 1856) 

 describe the formation of the sporangia and state that thej' 

 become separated from the parent filament by a partition. 

 The internal green mass resolves itself into zoospores 

 which escape e)i masse, afterwards separating from each 

 other, swimming actively apart. The authors were unable 

 to determine the cilia, nor did they follow out the sub- 

 sequent history of the zoospore. Schmitz (loc. cit.) added 

 some notes on the nuclei of the zoospores. 



In 1880 Berthold confirmed the occurrence of biciiiate 

 zoospores, but did not succeed in getting them to germ- 

 inate. On the other hand, he affirms the existence of 

 minute yellow biciiiate swarmspoores formed in quite 

 similar sporangia, and he states that he succeeded in 

 obtaining young plants only when both kinds of fructifica- 

 tion were present. 



Lastly, Went (Les modes de Reproduction du Codliini 

 tomentosum, Vergad. der Ned. Bot. Vereeii., 1881)) re-in- 

 vestigated the question and added new facts, lie confii'ius 

 Berthold on the question of the existence of large green 

 zoospores and small yellow ones, but he states that, con- 



