On the Nucleus of Synchytrium Puerariae, 



Miyabe. 



(Preliminary Note.) 

 By 



S. Kusano. 



With one Figure. 



On the cytology of Synchytrium, especially the structure of 

 the nucleus and the nuclear division, not much attention has 

 been paid as in the case of other groups of Phycomycetes. 

 Among the authors who have more or less concerned with the 

 cytologic al studies of this genus, Stevens seems to have laid 

 special stress upon the finer structure of the nucleus, not only 

 at the resting stage but also at the mitotic division. In Syn- 

 chytrium decipiens he mentioned, as unique phenomena, the early 

 dissolution of the nuclear membrane previous to mitosis, the 

 persistence of its remains as a granular halo aronnd the meta- 

 phase and anaphase figures, the peculiar mode of spirem and 

 spindle formation, etc. The writer found, during the phyto- 

 pathological study of a gall of Pueraria Thunbergiana caused 

 by Synchytrium Puerarix, that the fungus shows a close af- 

 finity in morphological as well as biological respects to 5. 

 decipiens. Especially the enormous size of its nucleus has drawn 

 the writer's attention and led to examine the behaviour of the 

 nucleus throughout the development of the fungus. The materials 

 were fixed with Flemming's mihIKkiskk's solutions. The sections 

 were stained with Flemming's triple stains or after Heiden- 

 miin's iron-haematoxylin method, and examined under high 



11 Dakgeard, Le Botaniste '-'. L890. i». 63; Rosen, Cohn's Beitrg. z. Biol. d. Pfl. 

 VI. 1893. )>. 237; Harper, Ann. of Bot. XIII. L897. i>. 467; Stevens, Bot. Gaz. 

 XXXV. L903. i». 405; Loewenthal, ZeitBchrift f. Krebsforschung III. 1905, Arcliiv 

 Pi i| i Lenkunde V. 1905. 



