CHYTRIDIALES 589 



(5-20 by 30-900 [x), pyriform (15-44 by 20-70 ;x), globose (10-70 [x in 

 diameter), or irregularly oval, with an apical convex operculum 4-8 jx 

 in diameter which is rarely persistent, occasionally proliferating; zoo- 

 spores globose, 5-6 ;x in diameter, with a single, rarely two refractive 

 globules 2-2.5 \x in diameter, upon discharge forming a temporary 

 globular mass at the orifice of the discharge pore; resting spore formed 

 from the intercalary enlargements of the rhizoidal system, hyaline, 

 smooth, globose (16-24 \i in diameter), oval (14-16 by 18-22 fx), 

 citriform, with a large refractive globule up to 15 [x in diameter or some- 

 times completely filling the spore, wall thickened, upon germination 

 functioning as a prosporangium and forming a thin-walled evanescent 

 sporangium. 



Saprophytic on vegetable debris, Karling (loc. cit.), Brazil; cello- 

 phane, R. M. Johns (comm.), United States. 



As Karling said, this species bears an astonishing resemblance to the 

 monocentric Cylindrochytridium johnstonii. 



Nowakowskiella macrospora Karling 



Amer. J. Bot., 32: 29, figs. 1-30. 1945 



"Rhizomycelium profuse, richly-branched, fairly coarse, tenuous 

 portions 2-6 [x in diameter; spindle organs nonseptate, oval (8-16 X 

 12-15 [x), broadly spindle-shaped (5-7 12-15 (x), elongate and fusi- 

 form (6-10 x 15-30 jx), or slightly irregular. Sporangia terminal or 

 intercalary, hyaline, smooth, usually apophysate, often slightly flat- 

 tened and elongated transversely to apophysis, spherical (14-40 \x), 

 oval (18-25 x 23-30 jx), pyriform (8-30 X 18-55 [x), or elongate 

 (10-20 < 30-60 [x), often with an elongate neck, 5-8 x 20-60 [x; 

 apophysis oval or nearly spherical, 8-20 [x in diameter, oblong, clavate 

 or elongate; operculum usually slightly sunken, often apiculate and 

 somewhat hat-shaped, 5-8 jx in diameter; sporangia sometimes becom- 

 ing brown, thick-walled and dormant in old cultures, functioning as 

 sporangia or prosporangia in germination. Zoospores slowly oozing 

 out and forming a globular mass at exit orifice, spherical, 10-12 (x, 

 with a large (3-5 jx), somewhat disc-shaped refractive globule, and 

 numerous minute granules at posterior end; flagellum 38-42 u, long. 



