Trichomonas vaginalis : Trichomonads are cyanophilic. flagellate protozoa, shape like a pear,varying in diameter from 15 to 30 microns.The nucleus is vesicular , pale,,eccentrically located , and the cytoplasm Sometimes contains eosinophilic granules. Leptothrix may be seen in association with T. Vaginalis; this finding alone is not diagnostic, but suggests the presence of trichomonads. They are seen here in a coccal background . Smears containing trichomonads often contain highly  eosinphilic mature squamous cells and the nuclei of the squames are sometimes surrounded by a small perinuclear halo.