389] STUDIES ON MYXOSPORJDJA—KUDO 151 



Vegetative form: Cysts spherical. Those in liver and intestine yellowish, 

 surrounded by an envelope composed of fibrous connective tissue. Second- 

 ary cysts are formed. Polysporous. 



Spore: Oval, in front view. Two ovoidal polar capsules convergent 

 at the slightly attenuated anterior end. Coiled polar filament visible. 

 Sporoplasm with an iodinophilous vacuole and two nuclei. Sutural edge 

 shows folds in some cases. Dimensions: length 13 to 17ju, breadth 8 to 

 10/i, thickness 5 to In, polar capsules 6 to Ifx long. 



Remarks: Compare with Myxobolus sp. Gurley on page 142. 



MYXOBOLUS sp. Southwell 

 1915 Myxobolus sp. Southwell 1915 : 312-313 



Habitat: Subcutaneous intermuscular tissue of Rasbora (Cyprinus) 

 daniconius Day; from a stream near Katwan, Mirzapore (U.P.), India. 



Vegetative form: 6 cysts found on four fish. The seat is immediately 

 below the scales, in the epidermis. Color milky white. Soft, flattened and 

 roughly oval in shape. Greatest length found, 1.1mm, No pigment was 

 present on the cyst. 



Spore : Two equal capsules, with a very short tail-like process. Sporo- 

 plasm with vacuole; iodine treatment could not be carried out. 

 Dimensions: length 13^, breadth I3fi, polar capsule 4)u by 4/i(?). 



Remarks: Dimensions, especially that of polar capsule seem to 

 be misprinted. Southwell gave one figure of a fish with a cyst near the 

 dorsal fin. He thinks that "it is quite possible that our parasites may 

 belong to Myxobolus cyprini." The incomplete observation without any 

 figure, leads the writer to leave the form also as Myxobolus sp. Southwell. 



MYXOBOLUS FUNDULI Kudo 



[Figs. 474 to 476] 



1915 Myxobolus musculi Hahn 1915 : 201-205 



1917 Myxobolus musculi Hahn 1917 : 91-104 



Habitat: Branchiae and muscle of Fundulus heteroclitus, F. majalis; 

 Woods Hole. Hahn claims that he succeeded in causing experimental 

 infection in F. diaphanus and Cyprinodon variegatus by inoculation. 



Vegetative form: Hahn uses quite a number of different terms from 

 those that are ordinarily used in describing Myxosporidia, without giving 

 any definitions. Naturally it is hard to put what he wrote in several pages 

 in the following lines. Granular vegetative forms produce a great many 

 pansporoblasts, each with a single spore. "Trophoplasm" is difficult to 

 stain. Size: 74 by 33n, 24 by I9fi. Cysts within and between the muscle 

 fibers, containing several hundred spores. 



Spore: Hahn's descriptions may be summarized as follows: Dimen- 

 sions: length 14.3^, breadth 6.7/x, thickness 6.7/t to 2/3 of width, polar 



