138 ILLINOIS BIOLOGICAL MONOGRAPHS [376 



Vegetative form: Thelohan gave no description. 



Wegener's observations are as follows: 



Cysts, white, 0.75 to 1.7mm. by 0.4 to 0.7mm. In sections, cysts are 

 shown to be surrounded by a thick (10 to 20/*, average 16/*) layer of connec- 

 tive tissue. Ectoplasm a thin (6 to 8/i thick) layer, exhibits a transverse 

 striation. The striation is often absent at places in ripe cysts. Endoplasm 

 finely granular. In young cysts, it is, however, reticulated, with nuclei of 

 1.5/i in diameter. 



Spore: Thelohan described as follows: Flattened ovoidal with pointed 

 anterior end. Shell smooth. No folds. Polar capsule comparatively large. 

 Dimensions: length 10 to 12/i, breadth 9/x, polar capsule 6/i. 



Cepede observed numerous spores in the liver and kidney of Gobio 

 gohio. Dimensions in vivo: length 10 to 12/i, breadth 9/*, length of polar 

 capsule 6/1. Polar capsules of equal size. Coiled polar filament distinct. 



Wegener's form: length 10.5 to ll/z, breadth 7.5 to 8/i, polar capsule 5 

 to 6/i by Zn. 



Remarks: Wegener recognized another form, which seems to be of very 

 rare occurrence and which can not be distinguished distinctly from the 

 above described form. Cysts at the end of the branchial lamellae. Size 

 1.7 to 2mm. in largest length. Spore resembles more closely the figure 

 given by Thelohan for Myxobolus oviformis than the above mentioned form 

 which he observed. A small intercapsular appendix (rounded) indistinct. 

 Sporoplasm comparatively small. Length 12.5 to 13.5/*, breadth 9/*, 

 polar capsule 7.5/i by 3/*. 



Habitat: Superficial musculature and subcutaneous tissue of Cyprino- 

 don variegatus; Woods Hole (August). 



Vegetative form: Cysts, not closed, but fungoid masses of an irregular 

 shape, varying in size from 4mm. by 2.5mm. to 10mm. by 4mm., projecting 

 as much as 3mm. above general surface of skin. The skin of the host overly- 

 ing these tumors, is more or less cracked and broken, the scales being 

 scattered. 



Spore: Elliptical in the front view; lenticular in side view. Shell 

 thick. Sutural ridge marked. Two polar capsules, convergent, at the 

 anterior end. Spores kept in alcohol, extruded polar filaments under the 

 action of iodine water and sulphuric acid. Sporoplasm with a large iodino- 

 philous vacuole. Dimensions: length 13.9/i, breadth ll/x, thickness 8/x. 



