1052 PARASITES OF PROTOZOA 



tions agree with those of Stein (1878, 1883) on the escape of minute, 

 flagellated organisms from the so-called germ balls. Cejp (1935) ob- 

 served two flagella on the zoospores of Sphaerita of Paramecium. Ivanic 

 (1925) stated that he repeatedly observed release of the flagellated 

 swarm sports of the parasite {Sphaerita?^ of Amoeba jollosi. 



Mattes (1924), however, though he found flagellated 2o5spores of 

 Olpidium amoebae of Amoeba sphaeronucleolus, failed to see any 

 flagella or motility in the spores of two Sphaerita species of the same 

 amoeba. The same is true of the observations of all other investigators 

 of the parasite in Protozoa. It appears that Sphaerita in endozoic Protozoa 

 lack flagellated zo5spores, and that most of those of free-living amoebae 

 also do. 



A central or eccentrically placed nucleus in the spore was reported 

 by Dangeard (1895) in Sphaerita of Euglena, and by Penard (1912) 

 in Sphaerita of Amoeba alba; and it was shown by Cejp (1935) in the 

 parasite of Paramecium. Mitchell (1928) noted a nucleus in the spores 

 of the chytrid of Euglena sa?i guinea, and he alone described any detail in 

 the nuclear structure. In sphaeritas of endozoic Protozoa, the nucleus 

 has not been found, and there appears to be a thicker spore membrane. 

 The membrane appears in optical section as a well-defined ring, espe- 

 cially in spherical spores. In elongated spores there is frequently a stain- 

 able area at one end, appearing often as a crescentic thickening, as in 

 Sphaerita (Fig. 217C) in Nyctotherus ovalis (Sassuchin, 1928a, 1934). 

 This structure was noted also by Becker (1926) in Sphaerita endamoebae, 

 by Yuan-Po (1928) in the larger species in Entamoeba bobaci, and by 

 Connell (1932) in Sphaerita of Gigantomonas lighti. It has been ob- 

 served by the writer in the parasites in a number of flagellates in ter- 

 mites. 



Rupture of the sporangium takes place in the cytoplasm of the host, 

 then the body of the host may rupture and the spores be released into 

 the water. In most instances no previously apparent pore or papilla has 

 been shown. Dangeard (1889b) stated that the zo5spores of Sphaerita 

 in Euglena sanguinea escape by a papilla at one end. Serbinow's ac- 

 count (1907) of an elongated or fusiform sporangium in Sphaerita in 

 E. viridis and E. sanguinea, with a short exit papilla at one or both 

 ends, does not apply to most forms that have been placed in the genus. 

 Sphaerita cannot, then, be diagnosed on the basis of this account, as 

 was done by Minden (1915), without excluding many forms. 



