124 R- KUDO. 



The dimensions of the spore vary to a greater extent than those 

 \vhich I recorded from 1919 material. In fresh state, the spores 

 measure 12.5 to 16.5 /JL in length by 4 to 4.6 n in largest breadth. 

 Some abnormally large spores reach 25^ by 10 /JL, which are 

 without doubt the products of monosporous sporogony. 



When the spores are treated with methylene blue, there 

 appears a deeply stained round body surrounded by less deeply 

 staining cytoplasm which I hold as the sporoplasm, while in the 

 remaining part, an irregular network becomes distinctly visible 

 which is the coiled filament. In larger spores, the polar capsule 

 does not seem to be present (Fig. 4, g) ; in the smaller ones, 

 however, it is distinctly recognizable (Fig. 4, /;., j, fc). When the 

 spores are kept in methylene blue, the polar capsule apparently 

 shrinks and one sees the latter and a rounded sporoplasm in 

 them (Fig. 4, j, k). 



When the spore is subjected to mechanical pressure the 

 filament becomes extruded. The average length of the filament 

 is considerably greater than that obtained from 1919 material 

 for which I gave 150 to 200 fj. as the average length. Measure- 

 ments of a larger number of spores with extruded filaments show 

 that they average 350 to 400/1 in length. Except its base, the 

 filament is of a uniform thickness which is less than one third of a 

 micron in pressure-Fontana-preparations. When the pressed 

 spores are mounted in a Lugol-gum arabic mixture and left for 

 two days, the spore membrane, the sporoplasm and the extruded 

 filaments take yellowish coloration. In such a preparation, the 

 filament is considerably thicker, as a result of the swelling due to 

 the medium used for the mounting (Fig. 5, a). 



Contrary to some authors, there is no thickening at the distal 

 end of the filament of the present form as was the case in all the 

 other species of Microsporidia which I have studied up to the 

 present (Fig. 5, /). Very rarely one sees a thick point at the 

 extremity of the extruded filament (Fig. 5, c), an examination 

 under a higher magnification shows, however, that here the 

 filament became probably broken during the extrusion and the 

 material which compose the filament became spread out as a 

 result (Fig. 5, e). 



Abnormal spores such as shown in Fig. 4, n-s are of frequent 

 occurrence. Normal spores appear irregularly slender in form 

 when fixed in smears with formol (Fig. 4, g-s). 



