114 ILLINOIS BIOLOGICAL MONOGRAPHS [352 



MYXIDIUM DEPRESSUM Paris! 

 [Figs. 277 and 278] 

 1912 Myxidium depressum Parisi 1912 : 287 



Habitat: Gall-bladder of Citharus linguatula Gthr.; Napoli (August). 



Vegetative form: Not observed. 



Spore: Fusiform with greatly attenuated extremities in front view; 

 flattened and curved in S-form in profile. The axis of polar capsules 

 parallel to each other. Coiled polar filament visible in vivo. Sporoplasm 

 with two nuclei, occupies the extracapsular cavity of the spore. Dimen- 

 sions: length 12 to 14^i, breadth 5.5 to 6tx, thickness 2.5 to 3^t, polar cap- 

 sules 5.5 to 6/x by 2.3;u, length of polar filament 30ju. 



MYXIDIUM OVIFORME Parisi 



[Figs. 279 and 280] 



1912 Myxidium oviforme Parisi 1912 : 287-288 



1912 Myxidium oviforme Auerbach 1912 : 39 



Habitat: Gall-bladder of Apogon rex mullorum Guv., Coris julis Gthr., 

 Gadus callarias L., Trutta salar L.; Napoli (August), Norwegian coast. 



Vegetative form: Unobserved by Parisi. Auerbach's observation is as 

 follows : 



Trophozoites, small ameboid, usually spherical. Size 10 to 12/i in 

 diameter. Monosporous (probably). 



Spore: Oval with rounded extremities, slightly pointed at the foramina 

 of polar capsules. Shell with numerous fine striations running longitudin- 

 ally. Polar capsules being often invisible, opening a little above and below 

 of the hypothetical horizontal plane. Sporoplasm fills the extracapsular 

 cavity of the spore, leaving little space at the extremities of the polar 

 capsules. Dimensions: length 11^, breadth 8 to 8.5/i, polar capsules 

 4.5/i by Six, length of polar filament 30 to 35ju. Auerbach's measurements: 

 length 12 to 13/^, breadth 8 to 9n, polar capsules about 4/x long. 



MYXIDIUM ANGUILLAE Ishii 



[Figs. 281 to 284] 



1915 Myxidium anguillae Ishii 1915 : 372-382 



Habitat: Integument of the side of the body of Anguilla japonica 

 Temm. et Sch.; Schizuoka, Nippon (October). Number of the cysts 

 visible to unaided eye, 10 and 9 on the left and the right side respec- 

 tively. 



Vegetative form : Trophozoites form white and sharply contoured cysts. 

 Cysts, spherical or oval, surrounded by a membranous connective tissue 

 (about 2ju thick) of the host. Protoplasm is clearly differentiated into 

 ectoplasm and endoplasm. Diffuse infiltration also occurs. Size measured 

 along the skin, 1.2 to 2mm. in diameter; in sections 1.174mm. by 0.658mm. 



