160 ILLINOIS BIOLOGICAL MONOGRAPHS [398 



Wegener writes as follows: The white cysts are elongated, 1.2 to 1.8mm. 

 long and 0.5 to 0.7mm. wide. 



Spore: Cohn mentions dimensions exactly the same as those of 

 Eenneguya psorospermica and can not distinguish the two species by the 

 spore. 



Wegener gives the following dimensions: length 30 to 40^, breadth 

 7 to 8jLi, length of the cavity of spore 15 to ISju, length of tail 15 to 25/i, 

 polar capsule 8/x by 2 to 3jli. 



HENNEGUYA MINUTA (Cohn) Labbe 



[Figs. 488 and 489] 



1895 Myxobolus minutus Cohn 1895 : 39-40 



1899 Henneguya psorospermica 



minuta Labb6 1899 : 102 



Habitat: Branchiae of Percafluviatilis L.; Frisches Haff, Lesina. 



Vegetative form: Cohn's description is as follows: Cysts oval and 

 small, difficult to distinguish them from those of Henneguya psorospermica. 

 Size, 130/x by llSyu. The parasite was met only once. But the number of 

 the cysts was far greater than that of Eenneguya psorospermica, often 5 to 6 

 on one lamella, reaching up to 200 cysts on a single gillarch. 



Spore: Cohn gives the following dimensions: total length (28 to 45m) 

 about 36ju, length from the tip to the end of cavity (20 to 28ju) about 26m, 

 breadth 10 to ll/x, thickness 8/x, polar capsule 11 to 14m by 2 to 2>yi, length 

 of polar filament 42 to 45m, length of tail (8 to 17m) 12m- Cohn gives a 

 figure (Fig. 489) of a spore with two vacuoles(?). 



HENNEGUYA OVIPERDA (Cohn) Labb6 



[Figs. 490 and 491] 



1892 



1895 Myxobolus oviperdus 



1899 Henneguya psorospermica ovi- 



perda 

 1904 Henneguya psorospermica ovi- 



perda 

 1911 Henneguya psorospermica ovi- 



perda 

 1911 Henneguya psorospermica ovi- 



perda 



Habitat: Ovary of Esox lucius L.; Switzerland, Berlin, Frisches HaflF 

 (all the year round), Upsala (May), Austria (December). 



Vegetative form: Cohn writes as follows: No real cyst exists. The 

 parasite occupies the ovum. 



Auerbach, however, mentions the presence of cysts m the connective 

 tissue and follicle epithelium of the ovary. Dimensions, 1mm. up to 5 or 

 6mm. in diameter. 



