Located in the south transept is a monument to Lady Dervorgilla of Galloway. Following the death of her husband Lord John Balliol in 1268, Lady Dervorgilla had his heart embalmed and placed into an ivory casket. In memory of her husband, Lady Dervorgilla founded the Cistercian abbey of Dulce Cor (Latin for Sweet Heart) in 1273. When she died in 1289, her body and her husband’s embalmed heart were laid to rest in front of the high altar in the presbytery. The original monument was destroyed at the Reformation in 1560 with a new one made by Abbot Gilbert Brown later in the century.
During clearance work in 1929, fragments of this second monument were discovered and reassembled in the south transept. The table monument is ornamented with square traceried panels containing shields and badges. A stone effigy rests on top of the table and depicts Lady Dervorgilla dressed in a gown and mantle and cradling her husband’s heart casket to her breast. The year of Dervorgilla’s death is incorrectly given in the inscription on the capstone which reads: “R VILLA FUDATRIX HUI MONASTII QUE OBIIT S M CCLXXXIIII” (Dervorgilla, foundress of this monastery, who died in 1284).