The temporal gland (see photograph) is an organ uniquely possessed by living elephants and extinct mammoths. … The gland is located on both sides of the head, just over the temporal arch, between the ear and the eye, its external appearance is a slit located in the temporal depression. The active phase of the gland is marked by swelling of the surrounding skin and an overflowing of a fluid which stains the skin black and smells very bad. Intermittent uncontrolled urine dribbling is also observer during this peak period.

Changthai.com. I love the fact that elephants, those lumbering beasts cursed with a long life and a memory that spans it, are the only animal with a temporal gland.