(Πτῷος), a son of Athamas and Themisto, from whom mount Ptoum and the sanctuary of Apollo, which was situated upon it, were believed to have derived their name. (Paus. 2.23.3; Apollod. 1.9.2.) Ptous also occurs as a surname of Apollo. (Paus. 4.32.5, 9.23.3.)