BLASTOCLADIALES 665 



long by 8-40 [i in diameter; sporangium cylindrical to globose, 15-105 

 [x in diameter, wall thin, smooth, with from one to three discharge 

 papillae; zoospores ovoid to ellipsoidal, 5.5-7 jx long by 3-4 \i wide, 

 with a long posterior flagellum and an anterior ring of refractive globules, 

 emerging in a quickly evanescent vesicle; resting spore borne like 

 the sporangium, 15 180 [jl in diameter, surrounded by the thin wall of 

 the container, clavate, with a rounded apex and a truncate base, wall 

 dark brown, thick, coarsely and irregularly reticulate, upon germination 

 forming posteriorly uniflagellate planonts which give rise to zoospore- 

 or resting-spore-bearing thalli, sexuality not known. 



On fly cadaver, Matthews {he. cit.), hempseed bait, bog soil, coll. 

 G. R. LaRue, Sparrow (1943: 418), United States; S6rgel(1952: 388), 

 France. 



Blastocladiella asperosperma Couch and Whiffen 

 Amer. Journ. Bot., 29: 588, figs. 29-35, 41, 43^45, 66. 1942 



"Thalli consisting of extramatrical stalked or sessile zoosporangia and 

 resting sporangia anchored to the substratum by rhizoids; single or 

 caespitose. Zoosporangial thalli spherical, ovoid, pyriform or nearly 

 cylindrical; sporangia spherical, pyriform, ovoid, sub-cylindrical or 

 irregular; 25-100 jji thick when spherical, up to 88 < 155 y. when ovoid 

 or pyriform ; stalk when present varying from a small basal part to a 

 long tube 30 x 150 [i, usually thickest just below the sporangium, fre- 

 quently with one to several rings just below sporangium. Sporangia 

 with one to several (up to 1 1 ) emergence papillae. Zoospores usually 

 becoming active in sporangium before emergence. The first spores 

 emerging in a spherical vesicle formed from the gelatinized tip. After 

 the vesicle bursts the spores remaining in the sporangium emerge 

 slowly and swim away immediately upon reaching the outside. Zoo- 

 spores 3.6-4.6 x 6-7 jx. Resting sporangial thalli similar in shape, 

 size and early development to the zoosporangial thalli; resting spo- 

 rangia not completely filling the case in which they are formed; 

 spherical, ovoid, pyriform or sub-cylindrical; outer wall yellow 

 brown and distinctly warted; 14-80 jj. thick on grass when spherical, 

 somewhat larger on hemp seed and spherical to oval in shape. Ger- 



