In our UML class diagram, we have days of the week as an enumeration. We have a class that has a parameter -day: DaysOfTheWeek. However we are uncertain whether we should connect the enumeration to the class with an arrow and if so what arrow?
By defining the parameter to be of type DaysOfTheWeek, you have created a dependency of that class on DaysOfTheWeek. You can visualize this dependency by drawing a dependency relationship (a dashed arrow with an open arrowhead) from the class to DaysOfTheWeek, but it is redundant, because the dependency is already in the model.
It is up to you to decide whether or not to do this. I would advise to make a decision in your design team to either always draw these dependency arrows between classes and data types or never.