White-tailed deer have five sets of external glands: 1) preorbital glands in the corners of the eyes; 2) tarsal glands on the inner surfaces of the hind legs; 3) forehead glands located, as the name implies, on the forehead; 4) metatarsal glands on the outer surfaces of the hind legs; and 5) interdigital glands between the hooves.

	PREORBITAL GLAND The preorbital gland, located immediately in front of the eye socket, is sometimes called the tear gland. However, the waxy substance in the preorbital gland serves as another means of identification through odor as the deer rubs his face against branches, shrubs and trees. The preorbital gland does not produce tears.
	TARSAL GLAND Tarsal glands are located on the inside of the hocks of both hind legs on bucks and does alike. During the rut, both sexes squat down and urinate on these glands and rub their hind legs together, which turns the glands from their normal white to dark brown or black. This process also helps deer locate one another during the rut.
	FOREHEAD GLAND As the name implies, the forehead glands are located on the buck's forehead, between the eyes and the bases of his antlers. When he rubs his antlers on shrubs and trees, he also rubs his forehead, leaving the identifiable scent of his forehead glands on them. Leaving his scent on shrubs and trees in this manner is like leaving his personal signature, so that other deer may know he has been there and personally made the rubs.
	METATARSAL GLAND The metatarsal glands are located on the outside of the lower hind legs of both bucks and does. They appear as round white puffs of hair. Their purpose is unknown at this time.
	INTERDIGITAL GLAND The interdigital gland is located in the cleft between the toes of the front hooves of both bucks and does. This gland also emits and odor which is left in the deer's track, enabling other deer to follow by smell. It appears that does leave an identifiable scent through their interdigital glands that tell a buck when they are ready to be bred. The buck singles this track out and follows it much like a dog sniffing his way along the ground.

Each gland secretes a different scent called a pheromone. The word pheromone [pronounced fair-a-moan] means a chemical substance that is produced by an animal and serves as a stimulus to other individuals of the same species for one or more behavioral responses.

These scents are part of a communication system that identifies individual animals.

Mechanisms for release of glandular secretions are not well understood by scientists. Both hormonal and sympathetic nervous stimulations may be involved.

In addition to the pheromones from the glands, deer use urine as a scent.

Fawns rub-urinate when they are frightened, and older deer do the same in aggressive situations.

During this behavior, the animals rub their hind legs together while urinating on the tarsal glands.

In white-tailed deer, the tarsal glands, interdigital glands and rub-urination serve the same functions. However, scientists have found the metatarsal scent does not produce an alarm reaction and whitetails seem to depend more strongly on behavioral clues, such as the raised tail, than on pheromones as alerts to danger. The preorbital glands are reduced in function to tear glands.