Full Cast & Crew

Cast(in credits order) verified as complete  

• 
  Hans Conried
  ...
  Narrator / Horton / Dr. H. Hoovey (voice)
• 
  June Foray
  ...
  Jane Kangaroo / Mother Who / Baby Who / Cindy Lou Who (voice)
• 
  Chuck Jones
  ...
  Junior Kangaroo / Various Whos / Quizmo McKwoff / JoJo (voice)
• 
  Thurl Ravenscroft
  ...
  Wickersham Brother (voice) (uncredited)