1068 AQUATIC PHYCOMYCETES 



minal vacuoles outlined by large, conspicuous, rounded, highly refrac- 

 tive granules, the latter also forming occasional isolated groups in the 

 hyaline cytoplasm. External hyphae one per internal segment, frequently 

 forming at adjacent sides of a cross wall, tubular, occasionally branched, 

 3-7.5 jjl in diameter. Conidia hyaline, spherical, 13.5-17.5 u,, usually 

 15 [ji, in water with a 5 y. long, basal papilla; germinating by a tube, 5 (x 

 in diameter, or forming secondary and tertiary conidia directly. End of 

 conidiophore swollen, 6-7.4 \i, at the base of the conidium and project- 

 ing into the undischarged conidium as a conical columella with a mi- 

 nute apical aperture ; swollen end cell of germ and infection tube 8-10 [i x 

 30-60 jjl; appressorium barely discernible or lacking. Conjugation lateral 

 or scalariform, gametangia developed simultaneously as lateral out- 

 growths from cells of the intramatrical hyphae and delimited by 1 or 2 

 septa depending upon their terminal or median position; male game- 

 tangium narrow, 3.5-7.5 \i, straight or slightly curved, female game- 

 tangium rounded and enlarged; fusion occurring near base of female 

 gametangium. Zygote developed in smooth-walled protuberance of the 

 female gametangium, separated from the main filament by a short stalk 

 cell; zygote or resting spore smooth, brown, thick-walled, spherical, 

 14.5-20 [x, usually 18.5 [j., filled with refractive globules, retracted slightly 

 from the enclosing cell, the latter forming an even, hyaline envelope; 

 germination unknown" (Berdan, loc. cit.). 



Parasitic in Closterium acerosum, Pfitzer (loc. cit.), Germany; Clos- 

 terium sp., Sorokin (1883:40, fig. 53), Asiatic Russia; Dangeard 

 (1886a: 314, pi. 14, figs. 1-10; 1889d: 203; 1890-9 lb: 93, pi. 4, figs. 

 19-23; 1903b: 216, pis. 6-8), France; Closterium sp., de Wildeman 

 (1889-90:135; 1893b: 62), Belgium; Closterium sp., Constantineanu 

 (1901 : 379), Roumania; Closterium spp., Petersen (1910: 542, fig. XVI, 

 F), Denmark; Closterium delpontii, Schultz (1923: 178, figs. 1-2), 

 Danzig; Closterium ehrenbergii Valkanov (1931a: 365), Bulgaria; 

 Closterium sp., Couch (in Berdan, be. cit.), C. striolatum, Berdan (loc. 

 cit.), Closterium spp., Under (1947: 244). Sparrow (1952d: 771), United 

 States; Closterium lanceolatum, Berczi (1940: 86), Hungary; Closter- 

 ium sp., Linder (F. 2597) (1947: 244), Canadian Eastern Arctic; Clos- 

 terium sp.. Canter (1 949d : 1 67, fig. 4), Great Britain ; Closterium lunula, 

 Hofler (1950; 381, figs. 1-4), Austria; Closterium sp., John (1955: 93, 

 figs. 1-12, pis. 5-8), India. 



