Which instrument is considered to be a bridge between the trombone and the trumpet?

I would have to say either valve trombone or baritone/euphonium.

150 e e e e e e e e e e e

White: titanium white.black: mars black.red: primary magenta, quinacridone red or alizarin crimson, cadmium red light.yellow: primary yellow, diarylide yellow, yellow ochre.blue: primary cyan, ultramarine blue, phthalocyanine blue.orange: pyrrole orange or cadmium orange.green: permanent green.