Entamoeba coli. Trophozoite and
cyst in fecal smear (trichrome stain, oil immersion). A trophozoite and uninucleate
cyst are seen side by side in this field. The trophozoite has a typical nucleus
with an eccentric karyosome and coarse, irregular chromatin. The cyst contains
a large glycogen mass that compresses the nucleus to the margin; chromatoid
bodies with splintered ends are present at the margin of the cyst.