PARASITES OF PROTOZOA 1043 



site described by Penard (1912) in A. tery'icola appears to be a chytrid, 

 but it is not like typical Sphaerita. 



There seems to be only one record of Sphaerita in a free-living ciliate 

 — the brief account of Ccjp (1935) of the parasite in Paramecium, up 

 to eleven sporangia occurring in a cell. Bodies like the sporangia of 

 Sphaerita, but with exit tubes, were shown by Collin (1912) in Acineta 

 tuberosa. Chytrids in other Suctoria, found by Claperede and Lachmann 

 and by Stein, are mentioned below (p. 1064) . 



Dangeard (1895) established the genus Nucleophaga for a parasite, 

 N. amoebae (not amoebaea as Penard, 1905b, and Doflein, 1907, have 

 it), which he studied in the nucleus of Amoeba verrucosa [A. proteus 

 according to Penard, 1905b). Gruber (1904) found Nucleophaga in 

 A. viridis, and supposed it to be different from Dangeard's species, but 

 according to Penard (1905b) it is probably the same. Penard described 

 N. amoebae in A. terricola and A. sphaeronucleolus; and Doflein re- 

 corded the parasite in A. vespertilio Penard. Mattes also found, in the 

 nuclei of A. terricola and A. sphaeronucleolus, parasites which he named 

 Sphaerita nucleophaga. He believed that the forms of Penard and Doflein 

 belonged to this same species, those of Dangeard and Gruber each being 

 a difl^erent species. Although he did not comment on the relationship of 

 the genera Sphaerita and Nucleophaga, his treatment of the chytrids 

 seems to indicate that he regarded the latter as synonymous with the 

 former. Indeed, no difference exists between the two except the habitat, 

 and the basis for their separation seems scarcely valid. 



In Endozoic Protozoa — Because most of the studies of Chytridiales in 

 endozoic Protozoa are comparatively recent, there have been few errors 

 of interpretation. At about the time when Stein was describing germ 

 balls in euglenid and other flagellates, Leidy (1881) observed what is 

 clearly Sphaerita in Trichonympha agilis. He "suspected that they are 

 masses of ova-like bodies or spores," but discussed them as inclusions 

 in the endosarc, not as reproductive elements, Casagrandi and Barba- 

 gallo (1897) described nuclei in E. coli containing small, round bodies, 

 equal in size, and sometimes so numerous as to fill the entire nucleus; 

 and they figured several of them in certain vegetative amoebae (PI. 2, 

 Fig. 13). These, as suggested by Cragg (1919), were doubtless para- 

 sites, probably Sphaerita, and not nuclear parasites; Cragg suggested also 

 that the account by Craig (1911) of vegetative schizogony in this 



