1030 



AQUATIC PHYCOMYCETES 



Fig. 86. Pythium 



A. Pythium monospermum Prings., sexual apparatus showing monoclinous 

 antheridium and plerotic inspissate walled oospore. B. Pythium angustatum 

 Sparrow, showing zoospore formation in an entirely filamentous sporangial 

 type. C. Motile and encysting zoospores of Pythium adhaerens Sparrow. D. 

 Cyst of zoospore of Pythium adhaerens undergoing repeated emergence, a 

 smaller zoospore nearly mature within a vesicle. E. Pythium gracile Schenk, 

 sex organs in algal cell, showing aplerotic, inspissate walled oospores. F. 

 Lobulate type of sporangium of Pythium aphanidermatum (Edson) Fitz., 

 forming zoospores in a vesicle at orifice of slender discharge tube. G. Sexual 

 apparatus of Pythium temie, showing monoclinous antheridium alleged to 

 lack a cross wall, and immature oospore. H. Pythium dissotocum Drechsler, 

 sexual apparatus showing monoclinous, crooknecked, inflated antheridium 

 making broad contact with oogonium. /. Pythium adhaerens Sparrow, showing 

 polyandrous condition, with aplerotic inspissate oospore. J. Sexual structures 



