Thelivingmorphologyandinfraciliatureofaheterotrichousciliate,Folliculinopsisproducta(Wright,1859)Frauré-Fremiet,1936,whichwascollectedfromthenorthcoastofChina,wereinvestigatedbyinvivoobservationandprotargolimpregnationtechniques.Asanewcontribution,aredescriptionispresented:largeFolliculinopsisofgreentodarkgreenincolor,800-1500μminsize;twoperistomiallobesofapproximatelyequalsize,300-400μminlength;adoralzoneofmembranellescontainingabout1000membranelles,lyingalonglobemarginsandexhibitingtwocircleswithinbuccalcavity;50-70somatickinetiesinmid-body;macronucleusminiliform,consistingofabout20beads;loricasmooth,vase-shaped,(300-500)μm×(90-130)μminsize,with5-12spiralridgesonnecktube;marinehabitat.