Xfiles question please help me?

theres an episode i want to watch it is the one about people having some root that is (persons neck) and they die from it. also looking for the episode where theres a midget demon killing a fat guy in the kiddy pool and in the end of that episode the midget demon visits a jail and kills a man in his jail cell. the third one in the beginning of the episode there is an person hiding in the closet from a another person but this person has something coming out of his mouth and kills the man in the closet instantly. the fourth episode something of a metal thing that was made from bone tissue they leave the metal thing alone in the hospital and it builds itself to a alien or something can't remember please help me find these four episodes.