The pineal gland (also called pineal body) is located in the midbrain and is one of the few non-paired structures of the brain. The pineal gland is part of the endocrine system and produces the hormone melatonin. Melatonin is associated with sleep patterns and circadian rhythms.
There are two ways to locate this gland in the sheep brain.
In the photo below the cerebellum is being separated from the cerebrum at the transverse fissure. The pineal gland is seen nestled at the top of the superior colliculi. 
In a brain that is bisected, the pineal gland (black pin) is found just behind the thalamas (white pin)
