What is Jane's surname in the Tarzan stories by Edgar Rice Burroughs?

Jane Porter (later Jane Clayton, Lady Greystoke) is a major character in Edgar Rice Burroughs's series of Tarzan novels and in adaptations of the saga to other media, particularly film.

Jane, an American from Baltimore, Maryland, is the daughter of professor Archimedes Q. Porter. She becomes the love interest and later the wife of Tarzan, and subsequently the mother of their son Korak. She develops over the course of the series from a conventional damsel in distress, who must be rescued from various perils, to an educated, competent and capable adventuress in her own right, fully capable of defending herself and surviving on her own in the jungles of Africa.