Photoreception and Entrainment of Cockroach Activity Rhythms.
In the cockroach there are two distinct sets of photoreceptors-the compound eyes and the ocelli-which may function as a sensory input whereby circadian locomotor rhythms are entrained by environmental light cycles. Surgical removal of the ocelli did not interfere with normal entrainment, but covering over the compound eyes effected a loss of entrainment.
Roberts
S K
SK