Jack first appeared in The Marvelous Land of Oz. Jack's tall figure is made from tree limbs and jointed with wooden pegs. He has a jack-o'-lantern for a head which is where he gets his name (unlike most jack-o'-lanterns, the seeds and other pumpkin guts were not removed). Jack is not known for his intelligence which seems to depend on the quality and number of the seeds in his pumpkin-head at that time. However, he manages to come up with random bits of wisdom and common sense often. For example, after bringing Jack to life, Mombi has the following exchange with him: