Copy after Jean-Baptiste Camille Corot

When a friend asked to copy one of his paintings, Corot would lend it, and some of the pictures he lent never came back. That is how Martin Dieterle, the Paris expert whose family has studied Corot's work for five generations, put it in 2012. He added that most copies after Corot were made while the painter was still alive, by pupils, friends and other painters working in his manner.

After Corot is the label a museum gives to such a picture. The composition is his and the brushwork belongs to someone else, usually someone with no name. It makes no claim that Corot ever touched the canvas, and that is what separates it from a picture attributed to him.

At the Museum of Fine Arts in Boston the label sits on copies whose originals the museum lists as untraced. One is a small view of the Tiber island in Rome, painted on paper and carrying a false Corot signature. Another is a road through the woods near Arras, with a rider and a group of peasants.