What member of the hip hop collective, Wu-Tang Clan, appears in the song "The Glide" on the Album "4:21... The Day After," but doesn;t get credited? 
4:21... The Day After:  U-God appears in the song "The Glide" but isn't credited. U-God: Lamont Jody Hawkins (born October 11, 1970), better known as U-God (short for Universal God), is an American rapper and member of the hip hop collective, Wu-Tang Clan.
U-God