188 ILLINOIS BIOLOGICAL MONOGRAPHS [426 



42(43) Length of polar capsule more than one-fourth of that of spore; spore 18 to 20^ 

 long, 5 to 6m broad 



Myxidium lieberkuhni Biitschli 1882 (107) 



43(42) Length of polar capsule less than one-seventh of that of spore; length 16 to 17/x, 

 breadth 5^ 



Myxidium mackiei Bosanquet 1910 (112) 



44(41) Spore variable in shape; S-form, straight fusiform, etc.; length 9.1/u, breadth 

 2 . 8fx. Vegetative form produces cyst 



Myxidium anguillae Ishii 1915 (1^4) 



Incompletely described species 



Myxidium sp. Gurley 1894 (109) 



Myxidium sp. Awerinzew 1908 (H^) 



Myxidium sp. Mavor 1915 (115) 



Genus SPHAEROMYXA Th61ohan 1892 



1( 6) Spore straight, not arch-shaped 2 



2( 5) Shell-valves symmetrical 3 



3(4) Ends of spore truncate ; stria tions longitudinal ; length 1 5 to 20//, breadth 5 to 6/* . 



Sphaeromyxa balbianii Thelohan 1892 (H^) 



4( 3) Ends of spore rounded; sutural plane forming some angles with longitudinal axis 

 of spore; striations transverse; length 12 to 14/x, breadth 9 to 10m 



Sphaeromyxa immersa Lutz 1889 (119) 



5( 2) Shell-valves asymmetrical; unstriated; ends less truncate; dimensions about 

 twice or three times larger than those of Sphaeromyxa balbianii 



Sphaeromyxa gaskrostei Georg^vitch (121) 



6( 1) Spore arch-shaped, not straight. . ^ 7 



7( 8) Shell-valves indistinctly striated; ends truncate; length 22 to 28m, breadth 3 to 

 4.3m 



Sphaeromyxa sabrazesi Laveran et Mesnil 1900 (120) 



8( 7) Shell-valves unstriated 9 



9(10) Spore extremely large; length 75 to 80m, breadth 18 to 20m; ends slightly tapering 



Sphaeromyxa exneri Awerinzew 1913 (121) 



10( 9) Spore less than 35m in length 11 



11(12) Extremities rounded; length 30 to 35m, breadth 8m 



Sphaeromyxa incurvata Doflein 1898 (119) 



12(11) Extremities truncate; sutural ridge often twisted in S-form; length 20.8 to 26m, 

 breadth and thickness 5 . 4m 



Sphaeromyxa hellattdi Auerbach 1909 (121) 



Genus ZSCHOKKELLA Auerbach 1910 



1( 4) Shell-valves unstriated 2 



2( 3) Openings of polar capsules on flattened side; spore large; length 16 to 28.8m, 

 breadth 13 to 18m 



Zschokkella hildae Auerbach 1910 (122) 



3( 2) Openings o^ polar capsules at pointed ends; spore small; length 11m, breadth 7m 



Zschokkella globulosa Davis 1917 (123) 



4( 1) Shell-valves striated 5 



5( 6) Openings of polar capsules at pointed ends; polar capsules spherical; spore larger; 

 length 10 to 14m, breadth 6 to 7m 



Zschokkella acheUognathi Kudo 1916 (123) 



Numbers enclosed in parentheses refer to the page of the article on which b found the description of the species 

 named. 



