72. Summary rejection. (1) If, memorandum of appeal is not filed as per provisions of rule 71 the appeal shall be entertained.   (2) The appellate authority may dismiss an appeal by an order in writing, if it is not field within the stipulated period of thrity days :        Provided that  the appellate authority may ,  in the interest of justice, for the reasons to be recorded in writing, condone the delay in cases where appeal is not filed within the stipulated period ;        Provided further that before dismissing an appeal, the appellant shall be given a reasonable opportunity of being heard and the order of dismissing the appeal, shall be made in writing by recording the reasons therefore.