Chapter XLI: Section 80: All the vertebrae join with their adjacent fellows through

the intermediation of certain intervertebral pads, and also articulate by small processes at either end at the upper side of the arch, the zygapophyses. The normals to the polished facets of these point, in the case of the anterior zygapophyses, up and in (mnemonic: ant-up-in), and in the case of the posterior, down and out. The student should make this, and the other features of vertebrae, out upon actual specimens.