Robert John Holthaus December 28 1928 August 2 1985 better known as Bob Holt was an American actor best known for his voice work Holts first film role came in 1950 acting as Octavius Caesar in Julius Caesar His career as a voice artist began with the 1968 short film Johnny Learns His Manners for which he provided all of the voices He later appeared in such works as Bedknobs and Broomsticks several animated television specials with Dr Seuss for example The Lorax 1972 Dr Seuss on the Loose 1973 The HooberBloob Highway 1975 and The Grinch Grinches the Cat in the Hat 1982 and the animated film version of Charlottes Web as Homer Zuckerman Holt appeared in a variety of different works including animated films for both adults the 1974 sequel The Nine Lives of Fritz the Cat and for children as well as voice and acting work in liveaction films for the blaxploitation film Abby Holt provided the voice of the Demon In 1975 he was the voice of Grape Ape on The New Tom and Jerry Show The same year Holt provided the voice of Avatar in Ralph Bakshis film Wizards Avatars voice was an imitation of actor Peter Falk In 1982 Bob Holt played the title role in Marvel Productions animated The Incredible Hulk 1982 TV series also in the process creating a library of stock roars that would be used for many years afterwards