Details 340 came from Fernand Khnopff's picture known variously as Art, The Sphinx or The Caresses (1896). It is in the Musees Royaux des Beaux-Arts in Brussels.
The first three correct entries came from Malcolm Smith of London SE5; Mrs L Hepburn of Chatham, Kent; and Clive Wilmer of Cambridge.
Each will receive a bottle of champagne, as will this week's winners. Answers, on a postcard (to arrive by Wed 2 Jul, please), to: DETAILS 342, IoS, 1 Canada Sq, London E14 5DL.