sentences:  Traditionally morphological characters of the basidia was used for the delimitation of the smut fungi group, but after a thorough investigation of the ultrastructural 
  characters the group was revised.With the use of electron microscopy, Bauer et al.1997 found two separates lines of the smut fungi, namely the Microbotryales (which is now moved to Puzziniomycotina) and the Ustilaginomycetes.