Claim not duly notified to be barred.

Every such claim other than the claim of the Government not communicated to the Manager within the time and in the manner required by such notice shall except as provided hereinafter, be deemed for all purposes and on all occasions, whether during the continuance of the management or afterwards, to have been duly discharged: Provided that when proof is made to the Manager that the claimant was unable to comply with the provisions of section 67, the Manager may receive such claim within the further period of two months from the expiration of the original period of two months.