790 AQUATIC PHYCOMYCETES 



SOROSPHAERA Schroeter 

 In Cohn, Kryptogamenfl. Schlesien, 3(1): 135. 1885-89 



"Cystosori one to several in a cell, predominantly of the shape of 

 hollow spheres or ellipsoids, but often extremely variable in size and 

 shape; presence of common enveloping membrane doubtful. Resting 

 spores oval, ellipsoidal, pyriform, pyramidal and urn-shaped with 

 yellowish-brown to brown, thin, smooth or verrucose walls; with or 

 without apical collar; producing a single biflagellate, heterocont zoo- 

 spore in germination. Evanescent thin-walled zoosporangia small. Plas- 

 modia one to several in a cell, large or small; schizogony present (?) or 

 lacking; producing a single cystosorus" (Karling, 1942d: 41). 



Type species: Sorosphaera veronicae Schroeter. 



SPECIES IN AQUATIC VASCULAR PLANTS 



Sorosphaera veronicae Schroeter 

 In Cohn, Kryptogamenfl. Schlesien, 3(1): 135. 1885-89 

 Parasitic in Veronica spp. 



Sorosphaera radicalis Cook and Schwartz 

 Ann. Bot., 43: 86, pi. 2, figs. 1-6. 1929 

 Parasitic in root hairs of aquatic grasses. 



IMPERFECTLY KNOWN GENUS OF THE PLASMODIOPHORACEAE 



? PYRRHOSORUS Juel 

 Bih. Kgl. Svensk. Vetensk.-Ak. Handl., 26, Afd. 3, No. 14: 12. 1901 



PYRRHOSORUS MARINUS Juel 



Op. dr., p. 12, pi. 1 



Thallus at first plasmodial, later fragmenting into free ellipsoidal or 

 fusiform naked uninucleate cells; sori from larger rounded mother cells, 

 about 8 [j, in diameter, which occur with the sterile fusiform cells; 

 sporangia naked, with orange granules, divided by three successive 

 divisions into a naked mass of eight rounded cells, which become the 



