306 AQUATIC PHYCOMYCETES 



cate wall, without discharge papillae, rhizoids hyaline, very delicate, 

 tapering, irregularly branched, arising from a small, subsporangial 

 apophysis; zoospores \—\ u. in diameter, uniflagellate; resting spore 

 asexually formed, 5-6 [x in diameter with a smooth wall. 



On filaments of Spirogyra, Brazil. 



Although the zoospores were observed, their method of escape 

 (whether through one or more pores) was evidently not noted. It may, 

 possibly, be a species of Phlyctochytrium. 



? Rhizophydium sp. Kobayashi and Ookubo 

 Rept. Osegahara Gen. Sci. Survey Comm., 1954: 575, fig. 18. 1954 



Sporangium spherical or broadly obpyriform, covered by low bulla- 

 tions and bearing a single (?) subapical, slightly elevated discharge 

 pore; endobiotic system a slender, short unbranched or onct-branched 

 rhizoid. 



On Chlamydomonas nivalis, "red snow," Japan. 



Observations on zoospore discharge are needed to validate this fun- 

 gus. From the nature of the wall of the sporangium it appears to be 

 a distinct species. 



On Marine Algae 



? Rhizophydium discinctum H. E. Petersen 

 Oversigt. Kgl. Danske Vidensk. Selskabs. Forhandl., 1905 (5): 484, fig. XI, 1-3 



Sporangium sessile, at first spherical or subspherical, becoming 

 somewhat angular with the formation at maturity of one or two sub- 

 apical or lateral papillae, 8-30 jx in diameter, resting on a broad base, 

 wall smooth, colorless, thick (1-2 jx or more); endobiotic part consist- 

 ing of a stout unbranched (?) tube; zoospores 1-5 fx in length, method 

 of discharge and flagella not observed; resting spore not observed. 



On Spongomorpha verna/is, H. E. Petersen (be. cit.), Denmark; 

 Acrosiphonia ineurva, coll. F. Borgesen, H. E. Petersen (he. cit.), 

 Norway; Ceramium diaphanum, Sparrow (1936b: 257, figs. 29-30), 

 United States ; Polysiplwnia sp., Aleem (1953: 13, figs. 27-28), Sweden. 



Petersen distinguished sporangia of two sizes: some 8-15 fx in diam- 

 eter on Spongomorpha, and others up to 30 [x in diameter on Aero- 



