Deer have seven types of external scent glands distributed across their bodies. These are the forehead glands (on the forehead), the preorbital glands (below the eyes), the nasal glands (inside the nostrils), the interdigital glands (between the toes), the preputial gland (inside the foreskin of the deer's penis), the metatarsal glands (outside of the hind legs), and the tarsal glands (located inside of the hind legs). Although it is not their primary function, the salivary glands also function as scent glands. Deer rely heavily on the scent glands to communicate with other members of their species, and possibly even with members of other species. A deer may rub its preorbital gland (e.g., on a branch) purely for pleasure.