CHYTRIDIALES 445 



chitinophilic counterpart of Rhizophlyctis rosea. The species failed to 

 grow on cellulose substrata and did not become colored under varying 

 light conditions. As in others of the genus, a very few sporangia form 

 from a local enlargement of the germ tube and, rarely, polycentric 

 thalli develop. 



Rhizophlyctis hyalina (Karling), comb. nov. 

 Karlingia hyalina Karling, Mycologia, 39:63, figs. 34-42. 1947. 



Sporangium smooth-walled, hyaline, spherical and 8-85 \x, oval and 

 7-20 by 10-35 [i, pyriform and 10-30 by 20-55 [x, fusiform, angular 

 or irregular, bearing one to seven exit papillae or tubes, 7-20 \x long 

 by 3-6 \x in diameter, the tips of which are filled with a glutinous plug 

 which may extend 4-10 u. beyond tip; rhizoids for the most part arising 

 from several places on the sporangium, main axes mostly coarse, at- 

 taining a diameter of 12 [jl, much branched and extensive, endooper- 

 culum hyaline, slender, delicate, shallowly convex, submerged in the 

 exit papilla or tube, 6 \x in diameter, upon emergence of zoospores 

 expelled and carried away; zoospores spherical, 4-5.5 \l in diameter, 

 with a single large refractive, hyaline globule 2-2.5 [i in diameter, 

 flagellum 30-36 [i long; resting spore not observed. 1 



Saprophytic in vegetable debris in moist soil, Karling (be. cit.), 

 Brazil. 



As in certain other species of this genus, the sporangium forms 

 typically from the body of the zoospore, which remains extramatrical 

 and from which rhizoids are produced. In rare cases, however, the 

 sporangia and rhizoids may develop intramatrically from a swelling 

 near the tip of a branched germ tube. Infrequently, polycentric thalli 

 with a large primary sporangium and a smaller one occur. 



Rhizophlyctis petersenii Sparrow 



Proc. Amer. Phil. Soc, 78 (1): 48, text figs. 3-4, pi. 3, figs. 1-7, pi. 4, fig. J. 



1937 

 (Fig. 28 A-D, p. 440) 



Sporangia spherical or irregularly shaped, smooth-walled, the spher- 

 1 See p. 444, note. 



