397] STUDIES ON MYXOSPORIDJA—KUDO 159 



Frisches and Kurisches Haff, Pregel, Masurische Seen (all the year round, 

 but rarer in Winter) Switzerland. 



Vegetative form: Thelohan's observations on the structure of the 

 cyst, are as follows: The surface of the cyst is covered by a layer, homo- 

 geneous, refringent and deeply stained, with which the cyst comes in 

 direct contact with the surrounding epithelial cells of the host. Inside 

 of this layer, there is a "pseudoectoplasmic" zone, in which the protoplasm 

 is dense at places, forming radiate irregular striations, enclosing numerous 

 irregular masses which are composed of apparently the same substance that 

 forms the external layer. Toward the central portion of the cyst, there are 

 masses of spores (Fig. 496). 



Cohn's descriptions are as follows: The purely white cyst is elliptical; 

 length 1.15mm. and breadth 0.85mm. The seat is under the epidermis. 

 It is surrounded by the host tissue with small, elongated and scattered 

 nuclei. The outer layer of the cyst is a thin membraneous protoplasm. 



Wegener writes as follows: The white cysts are round or elliptical, 

 usually on the upper end of the branchial lamella. Size of larger cysts, 

 1.5 to 2mm. long and 1.1 to 1.5mm. wide. 



Spore: Elongated; anterior part fusiform and anterior end blunt. 

 Polar capsules elongated and parallel to each other. Coiled polar filament 

 visible in fresh conditions. Shell unstriated. Dimensions: total length 

 AOfjL in average, largest breadth 7/^, length of polar capsule 7 to 8/x. 



Cohn's form is described by him as follows: Spore narrow with blunt 

 anterior end. Sporoplasm with 6 horns (no figure to explain this expres- 

 sion!). When kept in water, sporoplasm takes round form and becomes 

 highly refractive. Dimensions: length 29 to 38/x, length between the tip 

 and the posterior margin of the cavity (15 to 20^i) 18^, breadth 9 to 10^, 

 polar capsule (8 to llju) 9/x by 2^1, length of "starren Faden" 14;u, length of 

 tail 14 to 18m. 



Wegener's form is as follows: total length 35 to SSfx, breadth 7 to 8ju, 

 length of the spore cavity 15ju, length of tail 15 to 20jti, polar capsule 8/x by 

 2 to 3/x. 



HENNEGUYA TEXTA (Cohn) Labbe 



1895 Myxoholus textiis Cohn 1895 : 38-39 



1899 Henneguya psorospermica texta Labb6 1899 : 101 



1910 Henneguya texta Wegener 1910 : 82-83 



Habitat: Branchiae of Perca fluviatilis L.; Pregel, Frisches and 

 Kurisches Haff (all the year round). 



Vegetative form: Cohn observed as follows: Cyst distinctly elliptical. 

 Length 0.75mm., breadth 0.375mm. The cysts surrounded by a thick layer 

 of the host tissue. In the peripheral portion of the cyst, the protoplasm 

 exhibits a network-like structure which forms a fibrous structure further 

 inside, crossing the cyst at right angles to the long axis of the cyst. 



