The lumbar vertebras, five in number, are broad and solid, for the support of the superincumbent weight. The different elements which enter into their composition are less distinct than in the dorsal vertebras, in consequence of the coalescence of the pleurapophyses with the centra and with the dia-pophyses, and of the altered direction of the zyga-pophyses. The centra are broad and convex, though flattened anteriorly; the neurapophysial pedicles are constricted; the neural spines are compressed and quadrilateral. The process of bone, commonly called transverse, is the pleurapophysis, or abdominal rib ; and the nodule of bone lying to the outer side of the superior zygapophyses, and called by Cru-veilhier "apophysary element," is the diapophysis, which still exhibits traces of that tripartite efflorescence of the apex observed in the lower dorsal region. If, in the articulated skeleton, the eye be carried along the dorsal diapophyses, or transverse processes, the relation of this element to the pleura-pophysis will be seen without difficulty in the whole region. If it be wished to separate the whole lumbar, or abdominal rib, the misnamed transverse process must be sawn off from the diapophysis in such a way as to resemble the last dorsal pleurapophysis; in other words, a process of bone must be removed down to the sides of the lumbar centrum. We may then notice, in the remaining diapophysis, those three points above mentioned.