CHYTRIDIALES 177 



European and Asiatic Russia was said to form small uniflagellate 

 zoospores and larger biflagellate ones. Cornu observed a similar phe- 

 nomenon, but attributed the occurrence of the large spores to poor 

 environmental conditions. Sparrow (1932b: 273; 1936a: 425) has re- 

 corded this species from the United States and England, but no zo- 

 ospores were observed and the identifications are therefore subject to 

 doubt. 



Cornu's name was applied, in error, by Fischer (1882: 365) to a 

 similar-appearing parasite in Saprolegnia which forms biflagellate zoo- 

 spores. The findings of Foust (1937) and Shanor (1942c) indicate that 

 Cornu's observations on the uniflagellation of the zoospores of his 

 parasite are correct. If fractionation of the thallus in this species and 

 the following ones is definitely proved to occur after infection by a 

 single zoospore, they should be removed from Kozella and placed 

 in a new genus. 



Pringsheim, who, incidentally, figures zoospores killed with iodine 

 as uniflagellate, considered the fungus to be the antheridia of the 

 Saprolegnia. 



Rozella aciilyae Shanor 



J. Elisha Mitchell Sci. Soc, 58: 100, pi. 17. 1942 



"An endophytic parasite of Achlya flagellata causing very slight or 

 no hypertrophy. Young Plasmodium hardly distinguishable in the host 

 protoplasm, hyaline and very nearly optically homogeneous. Sporangia 

 formed in linear sori, cylindrical to somewhat barrel shaped, length 

 and width depending largely upon that of host hyphae; exit papillae 

 short, about 1.5 [jl in length, rupturing following gelatinization of the 

 tips. Zoospores swimming in a jerky and darting manner, ovoid, 2-3 

 X 3-4 (j. with a single refractive globule, single flagellum posteriorly 

 attached, usually 12-15 \x in length. Resting bodies produced in seg- 

 ments formed in host hyphae that resemble sporangial sori, each 

 segment containing from one to many resting bodies. Resting bodies 

 spherical to oval, 12.6-23.7 \x in diameter (not including spines), mostly 

 15.8-17.3 jj., usually covered with fine tenuous spines which commonly 

 measure about 1.6-2.3 ;jl in length, wall of mature resting bodies thick, 

 reddish-brown to amber brown in color. Resting spore germination 



