How does Kovaloff interact with the nose?

In Part II, Kovalev hastens to follow his nose, and addresses him tentatively. He addresses the nose as "My good sir," and begins haltingly to describe the problem. The nose does not understand and forces him to try to explain further. But they cannot reach a point of mutual understanding. Eventually, the nose tells him that he is mistaken, and he is his own person. What's more, the nose continues, the buttons on their uniforms are different and thus indicate different governmental departments. With that, the nose takes his leave. Kovalev stands there in shock.