32c World of Dinosaurs, Sheet of 15, Bottom or Top Halves Imperforate (3136p, 3136q). Two complete Mint N.H. sheets of 15, first with bottom seven stamps imperforate, second with top eight stamps imperforate, bright and freshVERY FINE AND RARE PAIR OF WORLD OF DINOSAURS SHEETS SHOWING BOTTOM AND TOP HALVES IMPERFORATE. ONLY TWO OF EACH ARE KNOWN.The Datz book states that there is only one sheet of bottom half imperforate and two of top half imperforate. However, we offer another bottom half impe