* @param key
   * @return Stella_Object
   */
  public static Stella_Object symbolProperty(Symbol symbol, StandardObject key) {
    { Cons plist = symbol.symbolValueAndPlist.rest;

      while (!(plist == Stella.NIL)) {
        if (plist.value == key) {
          return (plist.rest.value);
        }
        plist = plist.rest.rest;
      }
      return (null);
    }
  }