This is a fragment from the left side of the central panel of large altarpiece. It shows two saints at full-length. The nearer figure, Mamas, is a twelve-year old shepherd-boy who is shown in an olive-green robe, lined yellow-ochre, over a blue-grey coat and pale-brown hose; he holds a martyrs palm in his right hand. On the right, James the Greater is in a rose-red robe with a book in his left hand and a staff in his right. The lions visible behind the figures were an attribute of Saint Mamas, who was thrown to the lions in prison. The painting originally formed part of the Santa Trinità Altarpiece, an amply documented piece that was commissioned in September 1455 by the Company of Priests of the Trinity in Pistoia. The altarpiece represents the Trinity, and includes in the central panel the saints Mamas, James, Zeno and Jerome at either side of Christ on the Cross. In the predella below are scenes from the saints’ lives, including Mamas being thrown to the lions. When Pesellino died in July 1457, the painting was finished by Fra Filippo Lippi, and it was delivered in June 1460. The altarpiece was divided into several parts, probably in the 18th century, and has now been largely reassembled. This fragment is on long-term loan to the National Gallery, London, where it can be seen beside the other sections of the altarpiece.