Abstract: An apparatus for treating an endless textile web by passing it in a direction along an endless path and contacting it with a treatment fluid has a conveying nozzle provided with a housing traversed by the path and having a lateral inlet, an upstream tube and downstream tube longitudinally traversed by the path. The upstream tube has an upstream portion of a cross section decreasing in the direction and a downstream portion of substantially constant cross section and having a downstream end. The downstream tube has an upstream portion of a cross section decreasing in the direction and having an upstream end in the housing upstream of the downstream end of the upstream tube, spaced laterally outward from the downstream portion of the upstream tube, and forming with the downstream portion of the upstream tube a gap open into the housing and a downstream portion of cross section increasing in the direction.