THE PATHOGENIC RHIZOPODA 



301 



gromia. These grow to maturity and form gametes which escape 

 and conjugate in the surrounding water, the resuUing copula devel- 

 oping into a biflagehated organism which subsequently becomes 

 amel3oid and grows into an adult allogromia (Fig. 116). While 

 there is reason to doubt some of the developmental stages of this life 

 history, the essential fact remains that here is a clearly defined rhizopod 



"Allogromia," sp. (After Prandtl.) A, an individual from Ameba proteus with nucleus 

 undergoing fragmentation to form chromidia; B, aggregation of distributed chromatin into 

 secondary nuclei; C, A, Vampyrella, sp., infected with Allogromia, sp.; D, allogromia from 

 Ameba proteus shortly before ripening of tlie gametes. 



Fig. 117 



Binftle and multiple infection of ameba nuclei by Nucleophaga ameba-. (.Vfter P6nard.) 



one stage of whose life history is passed as an intracellular parasite. 

 The history of its nucleus is important as furnishing a po.ssible interpre- 

 tation of the distributed condition of the chromatin in neuroryctes and 

 cytoryctes. The cell plasm of this so-called allogromia becomes filled 

 with idiochromidia whicli are derived from the nucleus (Fig. 1 16, .1, B). 

 It is j)n)bable, as Dodeiii j^oints out, that this organism is not an 



