The =proximal sesamoids= are a little smaller, except in thickness. The =third sesamoid= or =navicular bone= is narrower and shorter. SKELETON OF THE OX VERTEBRAL COLUMN The vertebral formula is C_{7}T_{13}L_{6}S_{5}Cy_{18–20}. The =cervical vertebræ= are much shorter than those of the horse and are smaller in their other dimensions. The =articular processes= are smaller than in the horse, and a plate of bone connects each two of the same side. The transverse processes of the third, fourth, and fifth are double; the upper part projects backward, and is short and stout; the lower part is directed downward and forward, and is longer and more plate-like. The lower part of the sixth transverse process is a large, thick, quadrilateral and almost sagittal plate, directed downward. The seventh transverse process is single, short, and thick, and presents no foramen transversarium; it is in series with the upper part of the preceding processes. The =spinous processes= are well developed, and increase in height from before backward. They are directed upward and forward, with the exception of the last, which is nearly vertical and is about four or five inches (ca. 10 to 12 cm.) in height. The summit of that of the third bone is usually bifid. The =ventral spines= are prominent and thick in their posterior part; they are absent on the last two. The =atlas= has a large rough =tuberosity= on its dorsal arch. The =ventral arch= is very thick. The =wings= are less curved than in the horse, and the foramen transversarium (posterior foramen) is absent. The cavities for the occipital condyles are divided into upper and lower parts by a non-articular area, and are separated by a narrow interval below. The =posterior articular surfaces= are flattened behind and are continued into the vertebral canal, forming an extensive area for the odontoid process of the axis. The =axis= is short. The =spine= projects a little in front, and increases in height and thickness behind; its posterior border descends abruptly. The =odontoid process= (dens) is wide, and its upper surface is deeply concave from side to side. The =intervertebral foramen= is circular and not so close to the anterior border of the arch as in the horse. The =posterior notches= are not so deep. The =transverse processes= are stouter, but the =foramen transversarium= is small and sometimes absent.