i9i2] YAMANOUCHI—CUTLERIA 445 



I 



gave always and characteristically the form Falkenbergiana. In 

 1905 Satjvageau (47, 48) collected Aglaozonia melanoidea at 

 Banyuls-sur-Mer (Pyrenees-Orien tales), and in winter and early 

 spring in each successive year of 1905-1908, he (46-51) carried 

 on his cultures at the Laboratory Arago, Banyuls. From the 

 zoospores of Aglaozonia melanoidea he obtained, in a majority 

 of cases, Cutleria ads per sa, and in only one case out of 100 did he 

 obtain Aglaozonia melanoidea; but neither the form Churchiana 

 nor the form Kuckuckiana was produced. Unfertilized female 

 gametes of Cutleria adspersa produced either Aglaozonia or Cutleria. 



From his own results and those of previous investigations, 

 Sauvageau concluded that the alternation of two generations is 

 not necessary, but rather, as it might be said, facultative. Olt- 

 manns (35), from results of previous authors, considers Cutleria as 

 presenting no true alternation with the Aglaozonia generation, but 

 as simply presenting another instance of polymorphism in algae. 

 Strasburger (59), discussing the alternation of generations in 

 Phaeophyceae, agrees with the views of Sauvageau and Oltmanns. 



All these investigations, discussions, and conclusions were made 

 without any reference to nuclear conditions. The cytology of 

 Cutleria and Aglaozonia was first described by the author as a 

 preliminary note three years ago (74). 



The material for the present investigation was collected at the 

 Bay of Naples in the winter of 1908 and spring of 1909, during which 

 time I occupied a table of the Carnegie Institution at the Stazione 

 Zoologica. Cutleria tnultifida was found growing on rocks at a depth 

 of 1-5 meters in the vicinity of Posilipo and Castello dell 'Uovo, 

 and Aglaozonia reptans was growing on the surface of echinoderm 

 shells or stones in the same localities and also at Nisida along the 

 Bay of Naples, often at a greater depth. A fresh and plentiful 

 supply of material was furnished by Dr. Salvatore Lo Bianco 

 almost every day. Cultures of the plants and of their sporelings 

 and the fixation of their critical stages were made in the labora- 

 tory of the Station, where by the kindness of Drs. Anton Dohrn 

 and Reinhart Dohrn the author enjoyed every equipment for 

 facilitating the work. The investigation thus begun at Naples 

 was finished at the Hull Botanical Laboratory of the University of 



