468 
Ferdinandsen and Winge. — Clathrosorus , 
the parasite that the ripe sorus has the shape of an irregular, rounded or 
elongated ball with an uneven surface and traversed by larger and smaller 
cavities. The individual spores are not so solidly connected as, e. g., in 
Sorosphciera and Sorodiscus, where the spores are. conglutinated with a 
common substance. In contrast to the case in all hitherto known genera 
of Plasmodiophoraceae the spores have at the full maturity, but first then, 
a finely punctuate warty membrane. 
We have stated that the spores treated with Carnoy are somewhat 
collapsing, thus becoming flattened or depressed, and as if provided with 
a collar, while the spores preserved in diluted alcohol do not show this 
feature. Most of the other Plasmodiophoraceae seem to behave in the same 
manner. 
Below we give a diagnosis of the new organism. 
Clathrosorus, gen. nov. 
Spec. typ. : Clathrosorus campamdae , sp. n. 
Plasmodiophoracea radicicola, tumefaciens, cellulas corticis solum 
infestans. Amplificatio cellularum vix ulla. Sporosori in singulis cellulis 
sporosoro non impletis singuli, rotundati vel oblongi, saepe irregulares, 
clathrato-canaliculati. Sporae strato communi non conglutinatae, maturae 
globosae vel subglobosae,flavidulae, episporio subtiliter punctato-verruculoso. 
Clathrosorus campanulae, sp. nov. 
Statu vegetativo myxamoebae paulatim plurinucleatae in singulis 
cellulis corticis aggressu vix auctis singulae inventae, nucleum cellula 
hospitalis saepe amplectentes. 
Statu fructifero sporosori in singulis cellulis sporosoro non impletis 
singuli, transverse secti clathrato-canaliculati, desuper visi rotundati vel 
oblongi, foveolati et hinc circuitu irregulari, circ. 25-50 /ix lati. Sporae 
globosae nec non late ellipsoideae, siccitate fluidisve fixativis validis colla- • 
bescentes, sub vitro gregatim flavidae, singulatim hyalinb-flavidulae, epi- 
sporio subtiliter punctato-verruculoso, 4-5J M diametro. 
Ad radices Campanulae rapunculoidis quae aggressu parasitae eodem 
fere modo ac radices Leguminosarum bacilligerae intumescunt, in horto 
prope Soras Daniae. (Leg. H. Gram.) 
