The five succeeding cervical vertebræ are much alike, though each one has a certain individuality, by which its place in the series may readily be determined. The centrum has a convex anterior and concave posterior face, which in long-necked animals form regular “ball and socket” joints; neural spines are frequently wanting and, when present, are almost always short and slender; the zygapophyses are very prominent and are carried on projections which extend before and behind the neural arch; the transverse processes are long, thin plates and, except in the seventh cervical, are usually pierced by the canal for the vertebral artery, but in a few forms (_e.g._ the camels) this canal pierces the neural arch. (2) The dorsal or thoracic vertebræ have more or less cylindrical centra, with nearly flat faces, and on the centra, for the most part at their ends, are the concave facets for the rib-heads. The transverse processes are short and rod-like and most of them articulate with the tubercles of the ribs. The zygapophyses are smaller than in the cervical region, less prominent and less oblique; the anterior pair, on the front of the neural arch, face upward and the posterior pair downward. The neural spines are very much longer than those of the neck and those of the anterior dorsals are often of relatively enormous length, diminishing toward the hinder part of the region. [Illustration: FIG. 13.—Fifth cervical vertebra of Wolf, left side. _tr._, transverse process. _v.a″._, posterior opening of canal for the vertebral artery. _pr.z._ and _pt.z._, anterior and posterior zygapophyses. _n.sp._, neural spine.] [Illustration: FIG. 14.—First dorsal vertebra of Wolf, left side. _c._, centrum. _r._, anterior rib-facet. _r″._, posterior rib-facet. _tr._, transverse process. _pr.z_. _pt.z._, anterior and posterior zygapophyses. _n.sp._, neural spine.] (3) The lumbar vertebræ are almost always heavier and larger than those of the dorsal region; they carry no ribs and their neural spines and transverse processes are broad and plate-like and the latter are far larger and more prominent than those of the dorsals. As an especial degree of strength is frequently called for in the loins, together with a greater flexibility than is needed in the dorsal region, the modes of articulation between the successive vertebræ are more complex, sometimes, as in the Edentata, most elaborately so. Taking the dorso-lumbars, or trunk-vertebræ, as a single series, we may note that in a few mammals (_e.g._ the elephants) all the neural spines have a backward slope, but in the great majority of forms this backward inclination ceases near the hinder end of the dorsal region, where there is one vertebra with erect spine, while behind this point the spines slope forward. [Illustration: FIG. 15.—Third lumbar vertebra of Wolf, front end and left side. _tr._, transverse process. _cn._, centrum. _pr.z._ and _pt.z._, anterior and posterior zygapophyses. _n.sp._, neural spine.]