GUYANA 1981 (MNH) 15C ERYPHANIS POLYXENA WITH NON-SERIF AND SERIF OVERPRINTS
15c Eryphanis Polyxena pair with non-serif (type I) and serif (type II) 'ESSEQUIBO IS OURS' overprint respectively. Fresh and fine. Mint never hinged. SG808/a; SC391/a
Note: originally issued 1 October 1978 without overprint as part of the Butterflies definitive series
