9030 HEDOPHYLLUM SPIRALE, SP. NOV. ifl 



Ecldoniae in the tribe Lessoniideae?^ The union of both Costaria and 

 Cymatltere to Agariae is somewhat problematic, as Keinke seems to be 

 inchned to think so.^^ The reason upon which Setchell brought Thalassiopliyl- 

 lum near Agarum was in the similarity of the perforation in the blades of 

 the both genera. This view had been previously announced by Eosenthal.^' 

 But '' nach den Untersuchungen von Kosenthal dtirfte die Verwandschaft 

 von Thalassiophyllum und Agarum keine ganz nahe sein : endgtildige 

 Entscheidung wird wohl erst die Beobachtung der Jugendform von Thalas- 

 siophyllum bringen.^'^^ Happily Keinke's desideration has been brought 

 to eyes by Setchell and Gardner ; and the grouping of the both genera in 

 Agariae found another and more legitimate ground. 



About the systematic position of Hedopliylhcm, which was described 

 after the publication of '' Classification etc./' Setchell gives nothing. Keinke 

 mentions it under Laminareen which corresponds to Laminariae of 

 Setchell.^^ The erosion of the primary lamina, spiral rolling, and differen- 

 tiation of the of dorsiventrality in Hedopliyllum spirale suggest the close 

 relationship with Arthrotliamnus and Thcdassiopliyllmn ; and with Agarum 

 when we elliminate the first character. 



If the erosion of the primary lamina could be taken as an important 

 character in consideration of the natural order, the genus Eisenia shall be 

 detatched from the subtribe EcMonia, or EcJdonieen of Keinke, and 

 brought close by Artlwothavnnus or Hedopliyllum. 



Botanical Institute, Imp. Univ. Tokyo. 



Nov. 1903. 



LITEKATURE CONSULTED. 



Agardh. J. G. Species Genera et Ordines Algarum. I. 1848. 



„ De Laminarieis. 1867. 



Areschoug. J. E. Observationes Phycologicae. IV. V. 1883-1884. 



Collins, Holden and Setchell. Phycotheca Boreali Americana. VIII. 



1. On Calssification and Distribution. 



2. Stud, zur Vergl. Entwick. d. Lam. p. 20. 



3. Flora. 1890. p. 144. 



4. 8tud. p. 20. 



5. do. p. 18. " 



