Art. 1267.  Immovables in excess of disposable portion; collation by taking less.

If, on the contrary, the retrenchment of the excess over and above the disposable portion can not conveniently be made, the donee is bound to collate the excess by taking less, as is hereafter prescribed for the cases in which the collation is made of immovable property given him otherwise than as advantage or extra portion.