(2)"Where such a contract as above-mentioned is not reduced to writing, the company shall, within one month after the allotment, file with the registrar the prescribed particulars of the contract, stamped with the same stamp-duty as would have been payable if the contract had been reduced to writing, and these particulars shall be deemed to be an instrument within the meaning of the Indian Stamp Act, 1899, and the registrar may, as a condition of filing the particulars, require that the duty payable thereon be adjudicated under section 31 of that Act.