ORDER LAGENIDIALES 



101 



Fig. 32. Lagenidiales, Family Lagenidiaceae. (A-D) Lagenidium rabenhorstii Zopf. 

 (A) The coenocyte has divided into several zoosporangia. (B) Forty-five minutes 

 later, the cytoplasm is escaping from one of these zoosporangia into a vesicle. (C) Four 

 successive stages in the development of the same vesicle. (D) Plant with four empty 

 zoosporangia and an empty antherid and an oogone containing a mature oospore. 

 (E, F) Myzocytium proUferum Schenk. (E) Plant with empty zoosporangia, one with 

 a vesicle containing zoospores. (F) Plant with three antherids and three oogones con- 

 taining mature oospores. (After Zopf: Nova Acta Leopoldina, 47(4):141-236.) 



ments in the same hypha or in separate hyphae that are in contact may 

 function as antherid and oogone, respectively. They may be ahke in size 

 and other appearances or shghtly different. By means of a conjugation 

 tube the contents of the antherid pass into the oogone and then a thick- 

 walled, rounded oospore is formed. There is no distinct periplasm. 

 Germination of the oospore was described by Dangeard (1903) in Myzo- 

 cytium vermicola (Zopf) Fischer, which is parasitic in a free-living nema- 



