614.31  Forty-year chain of title.
  Any person who has an unbroken chain of title of record to any interest in land for forty years or more, shall be deemed to have a marketable record title to such interest as defined in section 614.29, subject only to the matters stated in section 614.32. A person shall be deemed to have such an unbroken chain of title when the official public records disclose a conveyance or other title transaction, of record not less than forty years at the time the marketability is to be determined, which said conveyance or other title transaction purports to create such interest, either in:
  1.  The person claiming such interest, or
  2.  Some other person from whom, by one or more conveyances or other title transactions of record, such purported interest has become vested in the person claiming such interest; with nothing appearing of record, in either case, purporting to divest such claimant of such purported interest.
[C71, 73, 75, 77, 79, 81, §614.31]