CZECHOSLOVAKIA. (Filed Post Offices). 1942. Registered Air Mail enveloped addressed to the 'Czech Military Mission. Montreal, Canada' bearing Great Britain SG 467, 3d violet (block of four),SG 485, 1/2d pale green and SG 489, 2 1/2d pale blue tied by framed 'Ceskoslvenska/Polni posta/ 22 July 1942/ Czechoslovakia Field' in violet with 'Opened by Examiner 3500' censor label. Very fine.