930 AQUATIC PHYCOMYCETES 



Resting spore predominantly ovoid, the brown wall covered 



with delicate evenly placed short spines .... O. pythii, p. 944 

 Resting spore with a companion cell 



Resting spore up to 24 (x in longest diameter, with curved flex- 

 uous-appearing intertwining spines up to 5 [t in length 



O. curvispinosa, p. 945 

 Resting spore up to 45 [x in longest diameter with straight 



spines less than 4 \i in length O. brevispinosa, p. 945 



Parasitic in Rhizophlyctis O. karlingiae, p. 946 



In fresh-water or marine algae 



In fresh-water algae; generally with a single discharge tube 



In diatoms (Gyrosigma) O. gillii, p. 946 



In green algae 



Resting spore and companion cell smooth-walled 



Resting spore filling the receptive cell; sporangia broadly or 



narrowly ellipsoidal; in Conjugatae . . . .O. schenkiana, p. 947 

 Resting spore lying loosely in the receptive thallus; sporangia 

 elongate, ovoid, saclike; in Oedogonium 



O. oedogoniarum, p. 948 

 Resting spore covered with long fibrils or spines, companion 

 cell smooth-walled 

 Resting spore covered with long delicate radiating fibrils 



O.fibhllosa, p. 950 

 Resting spore covered with spines 



Spines slender, companion cell long, vermiform 



O. appendiculata, p. 950 



Spines coarse, companion cell spherical O. zopfii, p. 951 



In marine algae; with one or more discharge tubes 

 Sporangia with one to seven long radiating discharge tubes; resting 



spore spherical or ellipsoidal, smooth-walled . . .O. andreei, p. 951 

 Sporangia with one (rarely two or three) short discharge tube; 



resting spore not observed O.feldmanni, p. 952 



Olpidiopsis saprolegniae var. saprolegniae (Braun) Cornu 



Ann. Sci. Nat. Bot., V, 15: 145, pi. 3, fig. 10. 1872 

 (Fig. 75 A-B, p. 939) 



Chytridium saprolegniae Braun, Monatsber. Berlin Akad., 1855:384; 



Abhandl. Berlin Akad., 1855: 61, pi. 5, fig. 23. 1856. 

 Diplophysa saprolegniae (Cornu) Schroeter, in Cohn, Kryptogamenfl. 



Schlesien, 3 (1): 195. 1885. 

 Pseudolpidium saprolegniae Fischer, in Rabenhorst, Kryptogamen- Fl., 1(4): 



35, fig. 3a-b. 1892. 



