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APPENDIX. 
Glossary of Terms relating to Schizogregarines. 
Anisogametes. Gametes showing sexual differentiation. 
Example : macro- and microgametes of Aggregata. 
Digenetic. Having two phases in the life-cycle, viz. schizogony and sporogony. 
Ectoschizous. Signifying that the schizont occurs on the outside of the cells of the host, 
and is attached thereto by cytoplasmic processes. In such cases the schizont is 
extracellular. 
Example : schizonts of Ophryocystis. 
Endoschizous. Signifying that the schizont occurs inside the host-cell, that is, the 
schizont is intracellular. 
Example : schizonts of Selenidium. 
Endogenous reproduction. The formation by the parasite of merozoites destined to re¬ 
infect the host. (See Schizogony .) 
Exogenous reproduction. The formation by the parasite of resistant spores destined to 
infect fresh hosts. (See Sporogony.) 
Gametes. Conjugating individuals developed from gametocytes, and giving rise to zygotes. 
Gametocyte. The adult trophozoite matured for the production of gametes. 
Gametogony. The process of gamete-formation. 
Gymnospore. “Naked spores”: not enclosed in a protective covering. 
Heteroic. When two different hosts are required for the evolution of the complete life- 
cycle of a parasite. 
Example : Aggregata. 
Homolc. When the life-cycle of a parasite is completed within one host. 
Examples: Ophryocystis , Selenidium. 
Isogametes. Gametes which are morphologically similar. 
Example : Ophryocystis. 
Karyosome. A nuclear corpuscle, containing a certain amount of chromatin in its 
substance, thereby differing from a nucleolus. 
Merozoite. A free-moving uninucleate individual resulting from schizogony. A merozoite 
is often club-shaped. 
Plasmotomy. The breaking-up of a multinucleate Protozoon into a number of portions 
or daughter-forms, each containing a variable number of nuclei. 
Example : Siedleckia. 
Schizont. A full-grown trophozoite which has exhausted its host-cell and is about to 
multiply asexually, that is, divide directly into numerous uninucleate parts 
(merozoites). 
Schizogony. A simple form of sporulation in which a trophozoite, without encysting, 
breaks up into numerous uninucleate masses of protoplasm termed merozoites. 
This process is sometimes called asexual multiplication or endogenous reproduction, 
and serves to increase the number of parasites in the host (auto-infection). 
