White collar tabs indicate military officers serving as Political Officers; bush jackets with no military insignia are apparently for civilian administrative staff. The officer seated here (standing in Y30469K/16) to the far right has lost his right forearm. The officer seated centre here (standing in Y30469K/16) wearing full military uniform, with ribbons but no cap badge or insignia of rank, is thought to be Hector (later Sir Hector, KBE) Livingston Duff (1872-1954). Duff served as Chief Political Officer with General Northey's forces in German East Africa 1916-1918 and administered the government of the occupied enemy territory. Later, he acted as Governor of Nyasaland. The officers to his right wear collar tabs but their cap badges etc. do not appear to be military - possibly, they are police officers seconded from Northern Rhodesia.