404 C. E. GATES. 



two sizes: the larger .O2-.O23 mm. long, the smaller .ooj-.ooS 

 mm. long. The contents of the spores are coarsely granular. A 

 single transparent vesicular body is present, centrally placed in 

 the small spores, eccentrically placed in the large spores. As no 

 other parasites with a cyst- or spore-forming habit are found in 

 segments three to five and as the spores are practically always 

 present with the trophozoites, it may be inferred, at least tenta- 

 tively, that they are produced by the trophozoites with which 

 they are always associated. 



Numerous specimens of the host have been dissected in every 

 month in which the worm can be obtained but only three cysts 

 from as many worms have been found in proximity to the 

 trophozoites. The cyst in each case was ovoid in shape and 

 about .62 mm. long. A tough membrane enclosed a fluid in 

 which floated two hemispherical bodies in contact with each 

 other on a flattened surface, nearly filling the cavity of the cyst. 

 After rupturing the membrane the gamonts were easily separated 

 from each other. The single hemisphere retained its shape and 

 opacity in clearing fluid. Rupturing the hemisphere by pressure 

 on the cover-glass released granules similar in appearance to 

 those found in the endoplasm of the trophozoite, but no nucleus 

 or spores could be seen. Spore-containing sporocysts have not 

 been found in the anterior segments but cysts about .75 mm. 

 long and .6 mm. wide, densely packed with spores similar in 

 size and appearance to those occurring in the anterior segments 

 are sometimes present in the whitish masses filling the ccelomic 

 cavities of the anal segments. 



Worms of the genus Eutyphceus occurring in Rangoon suddenly 

 disappear at the end of the rainy season and are not to be found 

 again until after the beginning of the next rainy season. The 

 failure to find the sporocysts in spite of the constant presence of 

 the spores may be due to a coincidence of the sporocyst formation 

 with this winter hibernation period of the host. 



SUMMARY. 



A new protozoan parasite of the ccelomic cavities of certain 

 tropical earthworms, with a remarkable branched structure of the 

 trophozoite is described. Mention is made of associated spores 

 and sporocysts possibly belonging to the trophozoites. 



