Raoul et al:
If memory serves me (maybe Chuck Schmidt can come up with a catalog) when they were first introduced, Unica was the saddle and Nitor made a proprietary seat post. The saddle was offered in both standard rails and the Nitor mounting frame. The Nitor frame was made of flat rectangular rails. At least that's my memory, but it was in 1961, and I only saw one of them. Campy was considered the way to go then, and the Nitor arrangement never caught on in Southern California. The "Unicantor" is a common mispronounceation.
Bill Curtis
Costa Mesa, CA