CHYTRIDIALES 379 



the species, E. vaucheriae is scarcely distinct from E. confervae-glome- 

 ratae save for the difference in host plant. It is probable that when 

 more is known about the resting stages of these fungi sharper lines of 

 specific differentiation will be revealed than are now apparent. 



The fungus in Vaucheria from England tentatively described as 

 Entophlyctis confervae by Sparrow (1936a: pi. 14, fig. 18), with spherical 

 sporangia and delicate isodiametric rhizoids arising laterally or nearly 

 basally on the sporangium, is distinct from this species. Since the resting 

 stage was not found, however, it is thought best to leave it unnamed. 

 It resembles the fungus called E. rhizina by Domjan (1936: 46, pi. 1, 

 fig. 137), see Figure 22 E, p. 371. 



Entophlyctis helioformis (Dang.) Ramsbottom 



Trans. Brit. Mycol. Soc, 5: 318. 1915 



(Fig. 22 G-H, p. 371) 



Chytridium helioformis Dangeard, Bull. Soc. Bot. France, 33:356. 1886; 



Ann. Sci. Nat. Bot., VII, 4: 293. 1886. 

 Chytridium heliomorphum Dangeard, Journ. de Botanique, 2: 143, pi. 5, 



figs. 19-23. 1888. 

 Entophlyctis heliomorpha (Dang.) Fischer, Rabenhorst. Kryptogamen-Fl., 



1 (4): 118. 1892. 



Sporangium spherical or ovoid, 6-20 \l in diameter, wall smooth, 

 colorless, somewhat thickened, discharge tube cylindrical, of variable 

 length; rhizoids unbranched or sparingly branched, arising from three 

 to twelve main axes formed at any place on the sporangium; zoospores 

 spherical, 3-4 \x in diameter, with a conspicuous centric or eccentric 

 colorless globule and a long flagellum, escaping individually upon the 

 rupturing of the tip of the discharge tube, movement swimming with 

 axial rotation, or amoeboid; resting spore borne like the sporangium, 

 spherical, subspherical, or broadly ovoid, 8-24 \x in diameter, with a 

 double wall, the outer thicker than the inner, contents yellowish, with 

 numerous oil globules, germination not observed. 



Saprophytic in Nilella tenuissima, Vaucheria sp., Chara sp., Dangeard 

 (be. cit.), France;? Chara spp., Nitella spp., Karling (1928a: 32, pi. 1, 

 figs. 1-35), Chara sp., Nitella tenuissima (?), Sparrow (1943: 260), 

 United States. 



