226 
A Myxosporidian 
the shell-valves of the spores of Sinuolinea dimorpha became separated from 
each other along the sutural line, and that when spores were subjected to the 
action of the fluid taken from the pyloric caeca of the host fish, the amoebulae 
emerged “in five to fifteen minutes” through the openings. Georgevitch 
(1917a) stated that he observed a similar separation of valves in the spore of 
Ceratomyxa coris. On the other hand, Erdmann (1912) describes an apparently 
abnormal occurrence in a spore of Chloromyxum leydigi. By adding to the spores 
placed on a slide first gastric fluid and then the bile of the host fish, she noticed 
the liberated binucleate amoebulae in the mixture, and stated that “die 
Sporenwande reissen (Fig. 8) nicht in der Nahtlinie, sondern in einer um 90° 
zu ihr geneigten Ebene.” The mentioned figure does not contain any of the 
four polar capsules, and may be interpreted as a case of separation of the valves 
along the sutural plane. 
Concerning the nuclear changes prior to and after the emergence of the 
amoebula, there are two views. According to Auerbach (1910, view 1) and 
Stempell (1919), the two nuclei of the sporoplasm fuse into one prior to 
the emergence of the amoebula. According to Auerbach (1910, view 2), 
Erdmann (1912 and 1917) and Georgevitch (1917 and 1917a), however, 
the fusion of the two nuclei takes place after the emergence of the 
amoebula. The nuclear changes in the present species agree with the latter 
view. 
Whether or not there is an intracellular stage in a Myxosporidian, the 
trophozoites of which live in the organ cavity of the host animal, has been 
the subject of study of several writers. The fact that Myxosporidia living in 
organ cavities of the host, may invade the tissues under certain conditions, 
was demonstrated recently by two examples. Debaisieux (1918) noted that 
Myxidium lieberkuhni Biitschli which is a well-known parasite in the urinary 
bladder of Lucius lucius, invades not only the lumina of the ureters and urini- 
ferous tubules, but also the glomerulus of the Malpighian body of the kidney 
of the host and develops into large cysts. I have also seen a similar case in 
Mitraspora elongata parasitic in the kidney of Lepomis cyanellus (Kudo, 1920a). 
Several investigators suggested the possible occurrence of an early intra¬ 
cellular stage in the Myxosporidia occurring in the organ cavities of the host 
animals. 
Not in many cases was this stage actually recognized. Regarding the young 
intracellular stages of Chloromyxum protei parasitic in the uriniferous tubule 
of Proteus anguinus, Joseph (1907) makes the following statement: “Ich fand 
ausgesprochene Jugendstadien anfangs regelmassig nur in den Zellen der 
flimmernden Anfangsteile der Nierenkanalchen, also in den Nephrostomial- 
und den Nebenkanalchen im Sinne der Nomenklatur von Felix.'' Auerbach 
(1910) observed in M. bergense and Zschokkella hildae that the uninucleate 
amoebula enters into the epithelial cell of the gall bladder or of the proximal 
portion of the gall duct of the host fish, although its significance was unknown. 
Examination of a large number of sections of kidneys infected by Leptotheca 
