An extraction hood of the up-and-down type for extracting fumes and/or vapours generated on a hob includes a fixed first hood portion (2) and a second extraction hood portion (4) set at a distance from the first extraction hood portion (2) and close to the hob, the second hood portion containing an extraction device (6) capable of drawing in air containing fumes and/or vapours from the hob and directing it towards an opening (11) in the second hood portion (4) to be discharged therefrom and passed towards the first hood portion (2). A conveyor (10) for the discharged air is provided at the opening (11) of the second hood portion (4). The conveyor includes a body (30) having a tubular annular shell (31) containing a honeycomb structure (32) with a number of tubular cells (42) through which the air leaving the second hood portion (4) is discharged.