The following photo presents a bit of historical Ambrosiana. I am told this shows a procession of the relics of Ss. Ambrose, Gervasius and Protasius through the streets of Milan, between the two great churches of Milan, the Basilica of St. Ambrose and the Duomo.
Looking at the photo, it would appear to the left that we are seeing some of the Ambrosian canons and/or prevosti, mitred and carrying what would appear to be the ferula -- a staff with an orb on top. (Click on the photo for a larger view.)