The mirror type eye of the scallop Argopecten irradians.

(A) Scallops have up to 200 single chambered eyes along their mantle edge, indicated by the white arrow. (B) The eye sits on a tentacle ( =  T) and the major internal structures of the scallop eye are indicated. C =  cornea, L =  lens, DR =  distal retina, PR =  proximal retina, M =  mirror, ON = optic nerve.