CHYTRIDIALES 273 



In contrast to Rhizophydium deformans (p. 243), no contortion of 

 the host trichome is produced by this species. 



The resting spore described was not associated with certainty with 

 the sporangial stage. Jaag and Nipkow believe their fungus to be 

 closely related to Rhizophydium sciadii Zopf but to differ from it in 

 having an unbranched rather than branched rhizoid. 



Rhizophydium sphaerocarpum (Zopf) Fischer 



Rabenhorst. Kryptogamen-Fl., 1 (4): 95. 1892 



(Fig. 17 L-M, p. 228) 



Rhizidium sphaerocarpum Zopf, Nova Acta Acad. Leop. -Carol., 47: 202, 

 pi. 19, figs. 16-27. 1884. 



Sporangium sessile, subspherical, ovoid, or urceolate, with a broad 

 (4-7 [jt, in diameter) protruding apical papilla, 6-18 \x in diameter and 

 up to 20 [i high, wall colorless, smooth, of two layers, the outer thicker 

 than the inner; endobiotic part consisting of a slender, generally un- 

 branched rhizoid; zoospores spherical or ovoid, 1.5-2 [x in diameter, 

 from a few to forty in a sporangium, with a colorless centric or slightly 

 eccentric globule and a long flagellum, emerging in an evanescent 

 vesicle, movement amoeboid or hopping; resting spore sessile, spheri- 

 cal, about 11-18 [x in diameter, with a thick smooth colorless wall, 

 contents with a large eccentric globule, rhizoid like that of the spo- 

 rangium, germination not observed. 



On Spirogyra, Mougeotia, Oedogonium, and other algae, Zopf (loc. 

 cit.), isolated from soil, Reinboldt (1951: 178), Germany; Mougeotia 

 genuflexa, coll. Marchal, de Wildeman (1890: 13, fig. 3), Belgium; 

 Mougeotia parvula, Atkinson (1909a: 326, fig. 3a-g), M. sphaerocarpa, 

 Mougeotia sp., Graff (1928: 161), United States; Oedogonium sp., 

 Skvortzow (1925:430), Manchuria; Spirogyra sp., Mougeotia (Go- 

 natonema) sp., Tokunaga (1934b: 390, pi. 11, figs. 6, 8-9), Japan; 

 Spirogyra maxima, Berczi (1940:82), Hungary; (as il Phlyctidium 

 sphaerocarpum"), Oedogonium, Spirogyra, Litvinow (1953: 79), Latvia; 

 pine pollen, Gaertner (1954b: 21), Equatorial East Africa, South 

 Africa, Gaertner (op. cit., p. 41), Sweden. 



This species, like Rhizophydium globosum, has become a collective 

 one, and a number of fungi with ovoid, spherical, or urceolate sporan- 



