CHYTRIDIALES 265 



12 [x in diameter, the upper two thirds of the wall covered with long 

 slender branched or unbranched hairs up to 30—50 [jl in length; rhi- 

 zoidal system delicate, profusely branched, arising from the tip of the 

 slender penetration tube; zoospores spherical, 3 u, in diameter, with 

 a single globule and a single posterior flagellum, discharged upon the 

 deliquescence of an apical or subapical papilla, the aperture thus 

 formed widening considerably after emergence of the spores; resting 

 spore epibiotic, spherical or slightly subspherical, \2\x in diameter, 

 with a thickened wall covered by short processes, long hairs, or both, 

 contents with a single large oil globule, rhizoidal system branched, 

 germination not observed. 



Saprophytic on Cladophora sp., Oedogonium sp., Sparrow (be. cit.); 

 saprophytic on vegetative filaments of Spirogyra sp., Oedogonium sp., 

 Sparrow (1952d: 762), dead internodes of Char a coronata, Karling 

 (1941b: 108), United States; Bulbochaete sp., Fott (1950: 7, fig. 20), 

 Czechoslovakia. 



In the ornamentation of its sporangium the species resembles 

 Chytridium chaetophdum Scherffel and Phlyctochytrium chaetiferum 

 Karling. The resting spores resemble those of an imperfectly known 

 species, Rhizophydium (?) setigerum Scherffel (1925b: 48, pi. 2, fig. 95). 



Rhizophydium keratinophilum Karling 

 Amer. J. Bot., 33: 753, figs. 1-43. 1946 

 (Fig. 18 I- J, p. 286) 

 "Sporangia sessile, hyaline, predominantly spherical (7-50 \x) with 

 2-5 fairly prominent exit papillae, 3-4 [j. by 4-6 \x broad; wall orna- 

 mented with short, simple bifurcate or dichotomously branched spines 

 (2-6(0. high) or long (15-45 \x), simple or branched threads. Rhizoids 

 fairly extensive (up to 120 u.) and richly branched; main axis up to 

 5 \i in diam. Zoospores spherical (2.5-3 a.) with a minute, spherical 

 (0.3-0.5 \x), hyaline, refringent globule; flagellum 10-13 \x long. Resting 

 spores spherical (7-15 [jl) or oval (5-6 X 7-14 u.) with a thick (2-3.5 \x) 

 brown, prominently-warted wall ; content coarsely but evenly granular, 

 growing out to form a superficial zoosporangium during germination" 

 (Karling, be. cit.). 



