. . . . . "Philadelphia Zoo" . "Philadelphia_Zoo#History" . "zoo" . . "Zoological Society of Philadelphia" . "Zoo" . . . . "1874" . . . . . . "Philadelphia Zoo" . "Philadelphia Zoological Garden" . . . . "Philadelphia_Zoo" . . . . . "Philadelphia Zoological Gardens" . . . . . . . "a zoo a mile from here" . . . "Philadelphia Zoo, The" .