France 1863 40c Indus Paquebot “Piroscati / Postali / Francesi” to Italy Cover

Folded cover, without contents, franked with 40c orange Napoleon, tied by dotted anchor cancel, postmarked with Indus ship mail cancel (24 Oct), struck with black boxed PD and "Piroscafi / Postali / Francesi", to Palermo, Italy, with indistinct transit and c.d.s. arrival backstamp (29 Oct), a visually-pleasing and scarce cover.