On a New Species of Chloromyxum from 

 the Gall-bladder of the Carp. 



By 



T. Fujita 



Tôhokii Imp. University, Sapporo. 



In view of the fact that Myxosporidiau parasite has never yet been 

 reported from the gall-bladder of the common carp, I deem it worth 

 while to give the following account of an apparently new Chloromyxum 

 species, which I have discovered in the said organ of that fish. The 

 species I propose to call C. koi, from the Japanese name of the host. 



During May, 1912. there came under my observation that, of the 

 numerous carps obtained in Sapporo, Hokkaido, and examined by me, 

 many were peculiarly pathologically affected. These showed gall- 

 bladder of an unusually reddish colouration, due to the contents being 

 of that colour ; moreover, it was generally found to be much dis- 

 tended, while the wall was changed into so delicate a texture that 

 it easily burst on application of a slight pressure. The peritoneal 

 membrane in the neighbourhood of the organ so aflected frequently 

 presented a somewhat greenish yellow hue, evidently as the result 

 of exudation of the bile. In certain cases a similar colouration was 

 also observable in the external skin of the dorsal body-parts and 

 sometimes even in the iris of the eyes. Now examining the gall-badder 

 of the fish presenting more or less the above icteric symptom, I have 

 always been able to discover peculiar Myxosporidiau sporoblasts and 

 spores floating in the contents. I have found that nearly \o% of the 

 carps that were brought to me were infested by the parasite. The 

 characters of the spores indicate that we have here to do with a 



