Answer:
Surmounted means "placed on top of"
Step-by-step explanation:
In this excerpt, the narrator describes the other character, Fortunato. This man was wearing "motley" (a piece of clothing made up of different colors) and a conical cap and bell "surmounting" his head. In this case, the verb surmount means to be on top of something tall or just on top of something.
Sometimes surmount can mean to overcome a difficulty, to deal successfully with an obstacle.