One of Burroughs's chief strengths is his ability to create fictional worlds vastly different from, but parallel to, the real world. The contrast between the "civilized" world of human s and the "uncivilized" world of the jungle runs throughout the Tarzan series. Burroughs's detailed descriptions of language, social behavior, and cultural traditions make his fictional society believable. ThroughoutTarzan of the Apes, Burroughs juxtaposes images of the two worlds, as when Tarzan , rightful heir to the Greystoke title, "wiped his greasy fingers upon his naked thighs and took up the trail of Kulonga . . . ; while in far-off London another Lord Greystoke . . . sent back his chops to the club's chef because they were underdone."