1912] GRIGGS—RHODOCH YTRIUM 169 
the nuclear cavity; it has no connection with the nuclear membrane. 
The spirem is formed from that part of the chromatin which lies 
in the equatorial region, the rest being cast. out; it is frequently 
entirely within the spindle. 
The second type of mitosis presents no unusual features. 
No centrosomes or true asters were seen. 
Amitosis is rare and abnormal in the zoosporangia. 
Although superficially resembling Entophlyctis, Rhodockytrium 
is not closely related to any known Archimycete. 
But it appears to be closely related to the Protococcoideae 
through Phyllobium. 
The Phyllobiae show considerable similarity to Synchytrium in 
gross morphology. 
The cytology of Riodochiiesan bears a strong resemblance to 
that of Synchytrium. 
These resemblances suggest that Synchytrium was derived from 
protococcoid ancestors. 
Onto STATE UNIVERSITY 
CoLuMBus, OnIO 
LITERATURE CITED 
1. Arkinson, Geo. F., A parasitic alga, Rhodochytrium spilanthidis, in North 
America. Bort. Gaz. 46: 299-301. 190: 
, Note on the occurrence of Rhodockytrium spilanthidis in North 
Ane: Science N.S, 28: 691-692. 1908. 
, Some problems i in the evolution of the lower fungi. Ann. Myc. 
7:441-472. figs. 20. 1909. 
, Some fungus parasites of algae.. Bot. Gaz. 48:321-338. figs. 8. 
1909. 
5. CHAMBERLAIN, C. J., The ovule and female gametophyte of Dioon. Bor. 
GAZ. 42:321-358. pls. 3. 1906. 
6. CoHN; peaaageane Ueber sss jaditecie Algen. Coxn’s Beitrige 17:87-108. 
pl. 3. 1872. 
7. DEBAISIEUX, Paut, Les ies de l’ovogenése dans le Dytiscus marginalis. 
La Cellule 25: 207-237. 
8. Grices, R. F., On the vata of Synchytrium. Yl. The réle of the 
centrosomes in the formation of the nuclear membrane. Ohio Nat. 
8:277-286. pls. 19, 20. 1908. 
, Some aspects of amitosis in Synchytrium. Bor. Gaz. 47:127-138. 
pls. 3, 4. 1909. 
2. 
3° 
4. 
