648 Ferdinandsen and Winge, — Ostenfeldiella , 
Here they divide, spreading only in the daughter-tissue of these initials, 
and being unable to reach either the outer cortex or the central cylinder. 
A rich intravaginal branching of the stem taking place near the growing 
apex, the branches naturally are in danger of being infected, and as 
Text-fig. 1 shows, this condition occurs, and may be supposed to be 
the rule. 
Finally we give a diagnosis of the parasite, which is, no doubt, a real 
Plasmodiophoracea. In honour of Dr. C. H. Ostenfeld, who discovered 
the fungus, and who also on former occasions has contributed to the know- 
ledge of these organisms, 1 we associate his name with our fungus, naming 
it : 
Ostenfeldiella , Ferd. et Wge. gen. nov. 
Genus caulicolum, submarinum Plasmodiophoracearum, Plasmodio- 
phorae propius accedens, colore autem saturato sporarum nec non modo 
crescendi proprio satis distinctum. Etymologia a cl. doctore C. H. Ostenfeld, 
fungi inventore, de studio plantarum maris vascularium optime merito. 
Ostenfeldiella Diplantherae , Ferd. et Wge. sp. nov. 
Myxamoebae uninucleatae in partibus merismaticis caulium hospitis 
nunc singulatim, nunc plures in cellula singula inventae, corticem interiorem 
solum infestantes. Ad basim internodii secundi myxamoebae plurinucleatae 
sese formare incipiunt, et in internodiis sequentibus sporosori, cellulas 
pluries auctas, 125-200 [x diametro, totum implentes, iacent. Sporae glo- 
bosae, 4-4J /x diametro, siccitate collabescentes, singulatim brunneolae, 
gregatim saturate brunneae, membrano satis crasso indutae, plasmate oleoso, 
flavescenti, refringenti farctae. 
In internodiis brevibus caulium ascendentium limo sepultorum Diplan- 
therae Wrightii Aschers., qui aggressu fungi ad modum siliquae Ornithopodis 
sativi usque ad 3 mm. diametro intumescunt, ad litus insulae St. Crucis 
Indiae occidentalis (Leg. C. H. Ostenfeld). 
Copenhagen, 
May, 1914. 
1 See 0 . Winge, 1 . c., p. 16, and C. Ferdinandsen et 0 . Winge: Plasmodiophora Halophilae 
sp. nov. Centralbl. f. Bakt., Parasitenk. u. Infektionskr., Bd. xxxvii, 1913, p. 167. 
