The dolmen shield of Ile-Longue. 

The best preserved example of the shield, the basic motif used in Armorican megalithic art, can be found on the Ile-Longue dolmen
The quadrangular body of the cartouche is separated from the rounded upper part, ending in a 'beak', by two 'notches'.The motif also contains radiant lines and lateral crescents. The shield can be seen as the oversimplified representation of a human body, with a head, hair, two shoulders and arms.
The overall effect produced by this unusual figure is emphasized by the scutiform slab it is engraved on.
Three other less elaborate 'shields' can be found in the monument. One can be seen almost facing the most elaborate specimen at the entrance to the passage. The location of the other two, on lintels of the ceiling, close to the engraving of a bow, indicates that they might have been re-used several times.