"Side view of skull of horse, with the bone removed so as to expose the whole of the teeth. PMx, premaxilla; Mx, maxilla; Na, nasal bone; Ma, malar bone; L, lacrymal bone; Fr, frontal bone; Sq, squamosal bone; Pa, parietal bone; oc, occipital condyle; pp, paroccipital process; i, the three incisor teeth; c, the canine tooth; pm1, the situation of the rudimentary first premolar, which has been lost in the lower, but is present in the upper jaw; pm2, pm3, and pm4, the three fully-developed premolar teeth; m, the three true molar teeth." — Encyclopedia Britannica, 1893

Horse Skull

"Side view of skull of horse, with the bone removed so as to expose the whole of the teeth. PMx, premaxilla;…