http://upload.wikimedia.org/wikipedia/commons/c/cf/Gray896.png

Lobular organ the parenchyma of which consists of glandular acini which communicate the lacrimal sac. Examples: There only two instances, right lacrimal and left lacrimal glands., The preorbital gland is a paired exocrine gland found in many species of hoofed animals, which is homologous to the lacrimal gland found in humans. These glands are trenchlike slits of dark blue to black, nearly bare skin extending from the medial canthus of each eye. They are lined by a combination of sebaceous and sudoriferous glands, and they produce secretions which contain pheromones and other semiochemical compounds. Ungulates frequently deposit these secretions on twigs and grass as a means of communication with other animals. The preorbital gland serves different roles in different species. Pheromone-containing secretions from the preorbital gland may serve to establish an animal's dominance (especially in preparation for breeding), mark its territory, or simply to produce a pleasurable sensation to the animal. Because of its critical role in scent marking, the preorbital gland is usually considered as a type of scent gland. A further function of these glands may be to produce antimicrobial compounds against skin pathogens. Antimicrobial compounds found in these glands may be biosynthesized by the animal itself, or by microorganisms that live in these glands[Wikipedia:Preorbital_gland].

uberon

glandula praeorbitalis, preorbital gland, tear gland

UBERON:0001817

https://github.com/obophenotype/uberon/wiki/Modeling-paired-structures-Design-Pattern

Innervation is highly complex and species-specific, In humans, they are situated in the upper, outer portion of each orbit

• lacrimal vein

• lacrimal nerve

• lacrimal artery

• secretion of lacrimal gland

• acinus of lacrimal gland
• lacrimal gland epithelium