The narrower partly blocked arch to the right has two arched niches under the present large plate-glass window. These niches were blocked up and covered by plaster bearing painted decoration imitating polychrome marble work, and this looks 7th century. Near the altar is a side door with a marble Baroque doorcase, and above this is a black marble tablet in a yellow Siena marble frame which commemorates Cardinal Francesco Adriano Ceva, who died in 1655. His memorial is the left hand one of the matching pair that flank the altar.