CHYTRIDIALES 249 



sile, hyaline, smooth, spherical (7-42 \i), oval or slightly flattened (7-15 

 X 10-24 [jl), with one to several low exit papillae. Zoospores spherical 

 (2.5-3.5 [j.) , with a minute refractive globule; emerging from one or 

 more of the exit papillae. Rhizoidal system richly branched; coarse- 

 ness, degree of branching, and length dependent to some degree on 

 size of host sporangia. Resting spores smooth, hyaline, spherical 

 (5-10 u.), oval or slightly angular, with one or more large refractive 

 globules; germination unknown" (Karling, loc. cit.). 



Parasitic on the sporangia and resting spores of Rhizophlyctis rosea 

 and Karlingiomyces granulata and on the sporangia of Septochytrium 

 macrosporum and S. plurilobulum (Karling, loc. cit.), Brazil; pine 

 pollen, Gaertner (1954b: 21), South Africa. 



With respect to this species, Karling says that the parasites found 

 on Septochytrium differ somewhat from those on Rhizophlyctis and 

 Karlingiomyces. Hence, it is not absolutely certain that they all belong 

 to the same species. 



Rhizophydium sphaerotheca Zopf 

 Abhandl. Naturforsch. Gesell. Halle, 17: 92, pi. 2, figs. 33-41. 1887 



(Fig. 17 D-E, p. 228) 



Sporangia sessile, single or in groups, spherical or subspherical, 

 with from two to five protruding papillae (one in smallest sporangia), 

 small plants, 4-5 [jl in diameter, largest seldom exceeding 22 \x, wall 

 smooth, colorless, distinctly double-contoured; rhizoidal system arising 

 from a main axis, much branched; zoospores few in small sporangia, 

 up to three hundred in large ones, spherical or ellipsoidal, 2.5-3 \j. 

 in diameter (see below), with a relatively large eccentric colorless 

 globule 0.9-1.2 [jl in diameter, a minute shining granule, and a deli- 

 cate flagellum, emerging from the sporangia through comparatively 

 large, circular, occasionally slightly protruding pores formed upon the 

 deliquescence of the papillae, movement amoeboid as well as swimming; 

 resting spore not observed. 



On microspores of Isoetes lacustris, I. echinospora, pollen of Pinus 

 spp. {P. sylvestris, etc.), Zopf (op. cit., p. 82, pi. 1, figs. 1-6, 16 a-c), 

 isolated from soil, Reinboldt (1951: 178), Germany; gymnospermous 

 pollen, Pseudotsuga mucronata pollen, Graff (1928: 161), pine pollen, 



