Cornual process

In Bulls, the frontal bone is very vast. The dorsal or frontal surface forms with the one of the opposite side a vast region that extends from the base of the nose to the top of the skull, filling more than the half of the dorsal surface of the head. It even rejects the parietal and occipital bones on the nuchal surface, of which it fills the dorsal border. At this level and very laterally, it holds the cornual process (Processus cornualis) that develops graduously during the first year of life and whose length and incurvation varies according to the race and the subject*; this eminence is very rough, sieved by small vascular holes and grooves, it is invaded by the cornual diverticle linked to the middle compartment of the caudal frontal sinus; its base is attached to the rest of the bone by the neck, a slightly shrunk part (Collum processus cornualis) above which appears the crown of cornual process (Corona processus cornualis), a soft annular bulge. From the base of a horn to the one of the opposite horn, the frontal bones forms, above the parietal bones, a thik transversal relief separating the dorsal surface from the nuchal surface of the cranium and fills the top of the skull: the intercornual protuberance (Protuberancia intercornualis). The external occipital protuberance and the nuchal line, that are rejected on the nuchal surface of the head, and the very short mastoid crest, that joins caudally the temporal crest, rise until the cornual process.

*Some bovine races have no horns, The morphology of the skull is then different, although the frontal bone stays broad.