↑Freud, Sigmund (1916). Leonardo da Vinci: A PSYCHOSEXUAL STUDY OF AN INFANTILE REMINISCENCE. New York: MOFFAT YARD & COMPANY. p. 39. Retrieved January 7, 2012. The situation contained in the phantasy, that a vulture opened the mouth of the child and forcefully belabored it with its tail, corresponds to the idea of fellatio, a sexual act in which the member is placed into the mouth of the other person.