124 ILLINOIS BIOLOGICAL MONOGRAPHS [362 



MYXOSOMA DUJARDINI Thelohan 

 [Figs. 341 to 343] 



Habitat: Branchial lamellae of Scardinius eryihrophthalmus L., Perca 

 tluviatilis, Leuciscus rutilus L. and Cyprinus carpio L.; France, Frisches 

 Haff, Kurisches Haff (February, April, May), Tokio (May), Switzerland. 



Vegetative form: White cysts being branched, rounded, spherical or 

 irregular; 1 to 1.5mm. in diameter. 



Wegener's form 1 to 1.7mm. long. 



Spore : Ovoidal, flattened, with attenuated anterior end which is slightly 

 bent laterally. Two pyriform polar capsules at the anterior end. Sporo- 

 plasm without any iodinophilous vacuole. Dimensions: length 12 to 

 13/x, breadth 7 to 8/i. 



Wegener's form: polar capsules 6// by 3^. 



Kudo's form: polar capsules 6 to 7/i by Iji, length of polar filament 70/x. 



MYXOSOMA (?) LOBATUM Nemeczek 



[Fig. 348] 



1911 Myxosoma (?) lohalum Nemeczek 1911 : 160-162 



Habitat: Branchiae of Leuciscus leuciscus L. and Aspius rapax Ag.; 

 Austria. 



Vegetative form: Cysts spherical, oval or elongated; of white color. 

 Size from 0.5 to 3mm. by 0.5 to 1mm. Those in Aspius rapax, oval to 

 spindle-shape, 1 to 3mm. long and 1 to 1.5mm. wide. 



Spore: Ovoidal; anterior end narrowly pointed and straight; posterior 

 end rounded, with lobose appendix (about 6ju long). A transverse fold 

 on the shell behind the polar capsules in fresh as well as preserved spores. 

 No iodinophilous vacuole. Dimensions: length 12.6;u, breadth 8.2ju, 

 length of polar capsule 4.2^4, length of polar filament 80 to 90/x. Spores 

 found in Aspius rapax, had slight difference in dimensions, the structure, 

 however, being similar to the above. 



Remarks: Nemeczek doubts if this form is really Myxosoma because 

 of the following: 1) different shape of the cysts compared with that of 

 the type species as described by Thelohan; 2) spores observed might 

 develop later into other forms like Henneguya. 



