The forehead region (Regio frontalis) is planiform, convex or concave according to the specie. It unites without any clear demarcation with the parietal planum and with the dorsal nasal region. On both sides, it is extended by the zygomatic process (Processus zygomaticus) of the frontal bone; this relief, simple spike that does not reach the zygomatic arch in Carnivorous, Porcines and Glires, is on the contrary important in Equidae and Ruminants, where it separates completely the entry of the orbit from the temporal fossa. This process determines the greater transversal width of the dorsal surface of the head; its caudal border is extended at the temporal line and the rostral border forms the supraorbital border (Margo supraorbitalis). Parallely to it spreads the relief of the eyebrow (Arcus superciliaris) which is discrete in animals; more medially stands the frontal bump (Tuber frontale). Dorsally to the orbit, more or less close to it or at the contrary from the median plane according to the specie, we find the supraorbital foramen (Foramen supraorbitale) sometimes multiple. In Ruminants and Porcines, this orifice ends in the longitudinal groove, the suprorbital groove (Sulcus supraorbitalis). Finally, the supraorbital foramen may be absent or replaced by a simple notch of the supraorbital border (Dogs, Cats, Rabbits, Men).