It is a stone bond in the shape of a herringbone, and found in carolingien (Carolingian) and préroman (Pre-Romanesque) buildings.
There is some confusion about this term in French Wikipedia. They distinguish "appareil en épi de blé" = stone bond in the shape of ears of wheat (opus spicatum) and "arête de poisson". The difference is that in case of arête de poisson the joint between the herringbones forms a straight line, while in opus spicatum it follows a zigzag line.
It is also used in pavements.
The picture shows this pattern in a (recent) piece of brickwork in the chauffoir (calefactory) of the abbaye (abbey) of Fontenay.
See also Arête de poisson.
|L'abbaye de Fontenay|