56 ILLINOIS BIOLOGICAL MONOGRAPHS [294 



Order MYXOSPORIDIA Butschli 1881 

 Suborder EURYSPOREA nom. nov. 

 Largest diameter of the spore at right angles to the sutural plane. 

 One polar capsule on each side of the plane. Sporoplasm with no iodin- 

 ophilous vacuole. Vegetative form found in body cavity (except 2 species) . 

 Great majority parasites of marine fish. Monosporous, disporous and 

 polysporous. 



Family CERATOMYXIDAE Dofiein 1899 

 With the characters of the suborder. 



Genus LEPTOTHECA Thelohan 1895 

 Shell-valves of spore hemispherical or shortly rounded, 15 species. 

 Disporous (7 unknown). 14 species in body-cavity; 1 in tissue; all in marine 

 fish. Type species: Leptotheca agilis Thelohan. 



Genus CERATOMYXA Thelohan 1892 

 Shell- valves, conical and hollow, attached on the bases; free ends 

 extended, tapering to more or less sharply pointed or rounded ends. 

 Sporoplasm usually does not fill the cavity, but is located asymmetrically 

 in it. 35 species. Disporous (23 species), monosporous and disporous 

 (3 species), disporous and polysporous (4 species) and unknown (5 species). 

 All (except 2 species in urinary bladder) in the gall-bladder of marine fish. 

 Type species: Ceratomyxa arcuata Thelohan. 



Genus MYXOPROTEUS Doflein 1898 emend. Davis 1917 

 Spores roughly pyramidal; with or without distinct processes from the 

 base of the pyramid. 3 species. Disporous (one species unknown). All 

 in urinary bladder of marine fish. Type species: Myxoproteus atnhiguus 

 (Thelohan) Doflein. 



Genus WARDIA nov. gen. 

 Spore form of isosceles triangle with two convex sides. Oval in profile. 

 Surface of shell with fine ridges which turn into fringe-like processes at the 

 posterior end. The polar capsules, large and perfectly spherical, situated 

 at the central portion of the spore, opening at the anterior tip. Two spe- 

 cies. Polysporous (one species unknown). Tissue parasite (one species) 

 of fresh-water fish and amphibia, both found in Illinois, U. S. A. Type 

 species: Wardia ovinocua nov. spec. 



Genus MITRASPORA Fujita 1912 emend. Kudo 

 Spores spherical or ovoidal. Two polar capsules pyriform, one situated 

 on each side of the sutural plane. Shell longitudinally striated; with or 

 without long and fine filaments projecting posteriorly in a row at right 



