PARASITES OF PROTOZOA 1051 



There is variability in the number of spores and the size of sporangia 

 within a species. That sporulation can occur at different stages of growth 

 was noted by Chatton and Brodsky ( 1909) , in Sphaerita of Vahlkampfa 

 Umax; sporangia ranged from 20 \\ in diameter down to small ones, 

 with few spores, of 4 |.|. Mattes (1924) stated that the size at which 

 sporulation starts in S. amoebae is very variable; and Lwoff (1925), in 

 Sphaerita of entamoebae of man, found that sporulated parasites are of 

 different sizes. The size of the sporangium and the number of spores 

 must not be used indiscriminately for definition of species. 



The spores are spherical, ovoidal, or ellipsoidal in shape — most fre- 

 quently the first. They range in size, in diflferent species, from a diameter 

 of 0.25 to 0.30 \\ {S. parvula, Brumpt and Lavier, 1935b) to elongated 

 forms of from 2.5 to 3 \x [Sphaerita from Euglena; Mitchell, 1928; Puy- 

 maly, 1927). Yuan-Po (1928) reported spores of from 2.5 to 4 |j in a 

 parasite of Entamoeba bobaci; this is exceptional in Sphaerita of endozoic 

 Protozoa. In the parasite of Nyctotherus ovalis, the spores measure from 

 1.5 to 2 n (Sassuchin, 1928a). Dangeard (1886a, 1886b) stated that 

 the spores of 5", endogena from amoebae have a size of 1.5 p. There ap- 

 pears in general to be only a limited variability in the size of mature 

 spores; but Becker (1926) found that in 5". endamoebae, the spores of 

 which usually were from 1.0 to 1.6 u, some were as small as 0.5 p. The 

 size and shape of spores is, used discretely, a valuable taxonomic guide. 



The spore of S. endogena in the rhizopods Nuclearia simplex and 

 Heterophrys dispersa has, according to Dangeard (1886a, 1886b), a 

 long flagellum ("cil") placed anteriorly and strongly recurved. Its 

 movements are very active and jerky, and sometimes there is simple 

 rotation in one position. When he studied the zoospores of Sphaerita 

 of Euglena sanguinea (1889b), Dangeard found, in addition to the 

 posteriorly directed flagellum, a very short one directed anteriorly. 

 Serbinow (1907) found only one flagellum on the zoospore of Sphae- 

 rita of Euglena, and thought it possible that Dangeard's biflagellate 

 zoopores belonged to some other organism, possibly to the parasite of 

 Sphaerita, Olpidium sphaeritae Dang. Serbinow described their jerky, 

 irregular movement. In Sphaerita of E. viridis, Puymaly (1927) also 

 reported biflagellate zoospores, the larger flagellum directed posteriorly, 

 as Dangeard noted again in 1895; and he described the movement as 

 rotation around an axis and rapid, oscillatory swimming. These observa- 



