THE CYTOLOGICAL DEVELOPMENT AND ENCAPSULATION OF MEGALOSCHIZONTS OF LEUCOCYTOZOON SIMONDI

Abstract

HCl hydrolysis of tissue sections before staining facilitated a detailed study of the cytological development of megaloschizonts of Leucocytozoon simondi in ducks. Schizogony is initiated when a fragment ("island") of a ruptured hepatic schizont is phagocytized. The "island" grows within the rapidly hypertrophying host cell and soon divides into smaller units, the cytomeres. These expand and subsequently infoldings or clefts subdivide each cytomere into smaller subunits. This partition continues and ultimately mature schizonts are filled with uninucleate merozoites.Evidence from study of the encapsulation of megaloschizonts suggests that capsule formation may be a passive as well as an active phenomenon, and is more pronounced in tissues with a dense reticulum.