405] STUDIES ON MYXOSPORIDIA—KUDO 167 



Vegetative form: Young trophozoites subcircular, irregularly elliptical 

 or elongated with distinct differentiation of protoplasm into ectoplasm 

 and endoplasm. Plasmotomic multiplication takes place during winter 

 months, when no spore is formed. 



Spore: Oval with short tail, mostly bifurcated at the free end. The 

 anterior end is more rounded, occasionally acuminated. Two polar capsules 

 of equal size. Coiled polar filament distinct in vivo. Sporoplasm granular, 

 contains two nuclei and a vacuole. The spore often shrinks in fresh con- 

 ditions, probably owing to the poorly developed thin valves. Dimensions 

 of spores mounted in balsam: length variable. Examples: Total length 

 22.5m, tail 8.5/i; total length 19.5pt, tail 8/i; length of main part 8.5/^, breadth 

 (comparatively constant) 6/*. 



HENNEGUYA ACERINAE Schroder 

 [Figs. 525 and 526] 



1906 Henneguya acerinae Schroder 1906 ; 186-196 



1910 Henneguya creplini Wegener 1910 : 84 



1911 Henneguya acerinae Nemeczek 1911 : 155 



Habitat: Branchiae of Acerina cernua L., Aspro zingel Cuv., Lucioperca 

 lucioperca L. and L. sandra Cuv. (?) ; Heidelberg (Necker), Apatin, Komitat 

 Baco-Bodrog, Hungary (May). 



Vegetative form: Schroder describes as follows: Rounded or spherical 

 cysts in the connective tissue of branchial lamella. Full-grown cysts up to 

 300/1 in diameter. Protoplasm is differentiated into ectoplasm and endo- 

 plasm. Ectoplasm shows fine radial striations. Endoplasm granular, 

 contains many nuclei, especially lying in the middle portion. Well devel- 

 oped cyst, containing only spores, is surrounded by a membrane. On the 

 surface of the ectoplasm, numerous edge-like elevations, branched and 

 joining together, were recognized. Polysporous. 



Nemeczek observed the largest cyst, spherical and 600// in diameter. . 



Spore: Pyriform in front view; flattened. The anterior end is more or 

 less blunt. Shell uniformly thin. Sutural edge slightly enlarged. Sporo- 

 plasm finely granular, contains an iodinophilous vacuole and two nuclei. 

 Polar capsules approximated closely, each having an independent opening. 

 Dimensions: length 20 to 22)li, breadth 8 to 9/i, thickness 6 to 7/x, length of 

 tail 50 to 60m, polar capsules lO/x by 2 to 3)u, length of polar filament 80 to 

 90/ii (water and nitric acid). 



Nemeczek's form is as follows: 



The tail is bifurcated along its entire length. In one case (May, 1909), 

 however, all the spores had no bifurcated tail, while the polar capsules were 

 of unequal size. Dimensions in fresh state: total length 37.6 to 41. 8/i, 

 length, excluding tail 12.6 to 16.8m, breadth 4.5/x, length of polar capsule 

 6.3 to 8.4jLi, length of polar filament 67/x, length of tail 25m. 



