Cartouche made to look like a drape hanging around scales of ancient units for measuring distance.
The cartographer for this series of maps was Jean-Baptiste Bourguignon d’Anville. Jacques-Philippe Le Bas seems to have been consistently responsible for the artwork, although his name doesn’t appear on every map. The publication date we mention is that which appears in the cartouche (i.e. not necessarily the publication date of the book the map refers to: we don’t know if the maps were included with the books or published separately).