R. Kudo 229 
that the gemmae are formed repeatedly one after another in one individual. 
Frequently one of the two generative nuclei, instead of developing into a 
spore, forms a gemma (Fig. 38). This appears to occur near the end of repeated 
gemmation. In such cases, after the liberation of the gemma, the mother 
trophozoite contains one spore and the vegetative nucleus (Figs. 38, 86). 
Davis (1916 and 1917) observed the formation of several gemmules in the 
polysporous trophozoites of Sinuolinea dimorpha and S. capsularis. In regard 
to the gemmation of the first named species, Davis writes as follows: 
Occasionally a degenerative cell is seen, in which division of the nucleus is not followed 
by a corresponding division of the cytoplasm. Successive nuclear divisions follow in rapid 
succession until eight nuclei are formed, all enclosed in a common cytoplasmic mass (Figs. 67 
to 71). Meanwhile, the entire structure increases considerably in size, forming a very charac¬ 
teristic rounded body, sharply marked off from the surrounding endoplasm (Figs. 59, 60, 
69 and 70). These bodies are probably homologous with the pansporoblasts but have a very 
different history from the ordinary structures of that name. They are, in reality, similar 
to the gemmules formed by many species of Protozoa. 
Although many other authors record the occurrence of plasmotomy in 
various species of Myxosporidia (Kudo, 1920a), the discussion of which is 
beyond the scope of the present paper, the above quoted observation of Davis 
deserves consideration here. Yet the two types of gemmation differ in several 
respects. In the first place, the character of the sporulation in the trophozoites 
differs in each case the one is polysporous ( S . dimorpha) and the other di- 
sporous (Z. ohlmacheri). In the disporous form of S. dimorpha , Davis did not 
see the process of gemmation. Secondly, the nature of the nuclei in the gemma 
and the number of gemmae formed at one time differ in the two forms. In 
this connection, it may be interesting to note that although the authors did 
interpret their observations in different ways, a study of their figures 
reveals cases in which gemmation similar to that of the present species 
may occur. For examples, the trophozoite of Ceratomyxa ( Leptotheca) coris 
which Stempell (1919) showed in his Figs. 54 and 116, contains a sharply 
outlined body which the said author interpreted as Vierergruppe.” One may 
say, especially after studying Fig. 116, that this appears to be a trinucleate 
gemma similar to that of the present species, since the nucleus located near the 
lower edge of the body seems to be that of a schizont of Nosema marionis 
which had been included in the cytoplasm of the gemma. Again, the disporous 
trophozoites of S. dimorpha shown by Davis (1916) in his Figs. 29 and 31, 
may represent stages of a gemmation similar to the above. Comparative 
study of the three species will probably lead to interesting results. 
This process of gemmation is of great significance to the parasite. As 
the Myxosporidian lives in the lumina of the uriniferous tubules of the host, 
possibly absorbing the waste matter secreted by the host cells, it is ad¬ 
vantageous that its body should remain small so as not to disturb the 
function of the host organ. By schizogony and gemmation, the number of 
the parasites will be greatly increased thereby maintaining the species 
