(2)(a)Every company having more than fifty debenture holders shall, unless the register of debenture holders is in such a form as in itself to constitute an index, keep an index (which may be in the form of a card index) of the names of the debenture holders of the company and shall, within fourteen days after the date on which any alteration is made in the register of debenture holders, make the necessary alteration in the index.(b)The index shall, in respect of each debenture holder, contain a sufficient indication to enable the entries relating to that holder in the register to be readily found.