What set Hsü Chih-mo apart from the others in the crowd when Yu-i’s boat docked?

From the text:

He was dressed in a long, narrow, black wool coat with a white silk scarf around his neck. I had never seen him in Western clothes but knew it was he. His carriage was unmistakable, so easy to spot, the only one in the crowd of receivers who looked as though he did not want to be there.