Section 22. Property held by the deceased as trustee

22. Property held by the deceased as trustee.—Property passing on the death of the deceased shall not be deemed to include property held by the deceased as trustee for another person under a disposition not made by the deceased or under a disposition made by the deceased where (whether by virtue of the original disposition or of a subsequent surrender of any benefit originally reserved to the deceased or otherwise) possession and enjoyment of the property was bona fide assumed by the beneficiary at least two years before the death and thenceforward retained by him to the entire exclusion of the deceased or of any benefit to the deceased by contract or otherwise: Provided that in the case of property held by the deceased as sole trustee for another person under a disposition made by himself, the period shall be five years.