1078 PARASITES OF PROTOZOA 



Ivanic (1936) stated that the parasite of Entamoeba histolytica, which 

 he described as Entafiioebophaga hominis, shows affinities to the Myce- 

 tozoa, but this is hardly apparent from his unconvincing account of the 

 structure and hfe history. The earhest stages are reported to occur 

 within the host cyst, and growth leads to an amoeboid body. At first 

 uninucleate, this becomes multinucleate. When the cytoplasm of the host 

 cyst has been largely consumed, the parasite breaks out and carries on 

 for a time an active, free-living existence in the intestinal lumen, as an 

 amoeboid organism. In this phase there is nuclear multiplication, binary 

 fission, growth to a giant, multinucleate plasmodium, and endogenous 

 budding. Ivanic found evidence that the organism was originally a 

 commensal of the human intestine before it became a parasite of £. 

 histolytica. This bizarre account probably contains a good deal of mis- 

 interpretation and confusion of distinct organisms. 



SPOROZOA 



The sporozoan parasites reported in Protozoa belong for the most 

 part to the Microsporidia and Haplosporidia. Dogiel (1906) assigned 

 to the coccidia a parasite, named Hyalosphaera gregarinicola, of a gre- 

 garine from a holothurian. Caullery and Mesnil (1919) considered this 

 systematic determination doubtful, but were certain that the parasite is 

 not a Metchnikovella. Dogiel described macrogametes, microgametocytes, 

 and sporulation, but did not observe schizogony. 



Four microsporidian parasites of Protozoa were listed by Kudo 

 (1924). Three of these are species of Nosema: N. n/arionis (Thelohan, 

 1895) Stempell, 1919, in the myxosporidian Ceratotnyxa (Leptotheca) 

 coris from the gall bladder of Coris julis and C. giofredi; N. balantidii 

 Lutz and Splendore, 1908, in Balantidii/ ni sp. from Bujo marines; and 

 N. jrenzelinae Leger and Duboscq, 1909, in the gregarine Frenzelina 

 conformis from Pachygrapsus marmoratus. The last species shows a 

 certain amount of correlation with the life cycle of the host, in that 

 sporulation occurs at the moment of encystation of the gregarine. The 

 gregarines develop normally up to a certain point; then the formation 

 of gametes does not take place (Leger and Duboscq, 1909a, 1909c) . The 

 fourth species, Perezia lankesteriae, also parasitizes a gregarine, Lankes- 

 teria ascidiae from Ciona intestinalis (Leger and Duboscq, 1909b). 



Microsporidia are probably much more widespread as parasites of 



