Initializing a static const array of const strings in C++

I am having trouble initializing a constant array of constant strings.

From week.h (showing only relevant parts):

class Week {
  private:
    static const char *const *days = { "mon", "tue", "wed", "thur",
                                       "fri", "sat", "sun" };
};

When I compile I get the error "excess elements in scalar initializer". I tried making it type const char **, thinking I messed up the 2nd const placement, but I got the same error. What am I doing wrong?