The =lumbar vertebræ=, six in number, are much longer than in the horse. The =bodies= are much constricted in the middle, expanded at either end, and bear rudimentary ventral crests. The fourth and fifth are usually the longest. The =intervertebral foramina= are often double in the anterior part of the series, and are very large further back. The =articular processes= are large, and their facets are more strongly curved than in the horse. The =transverse processes= all curve forward. They are separated by considerable intervals, and form no articulations with each other or with the sacrum. Their borders are thin and irregular, and often bear projections of variable size and form. The first is the shortest and the length increases to the fifth, the last being considerably shorter. The =spinous processes= are relatively low and wide, the last being the smallest; their summits are moderately thickened. The =sacrum= is longer than that of the horse. It consists originally of five segments, but fusion is more complete and involves the spinous processes, which are united to form a =median sacral crest=, with a convex thick and rough margin. =A lateral crest= is formed by the fusion of the articular processes. The =pelvic surface= is concave in both directions, and is marked by a central =groove=, which indicates the course of the middle sacral artery. The =inferior sacral foramina= are large. The =wings= are quadrangular, short, compressed from before backward, and high dorso-ventrally. They have an extensive anterior surface, which is concave from side to side, and non-articular. The posterior surface is rough, and bears a triangular area below for articulation with the ilium. The body of the first segment is very wide, and the entrance to the sacral canal correspondingly wide and low. The =anterior articular processes= are large, and are concave and semicylindrical in curvature internally. The =lateral borders= are thin, sharp, and irregular. The =apex= is wider than in the horse, and the posterior end of the crest forms a pointed projection over the opening of the sacral canal. The =coccygeal vertebræ= are longer and better developed than in the horse. The first five or six have complete arches and spinous processes. The transverse processes are relatively large in the anterior part of the series, in which there are also anterior articular processes (which do not articulate), and a pair of ventral spines which form a hæmal groove for the middle coccygeal artery. Vertebral curves: The cervical curve is very slight and is concave dorsally. The thoracic and lumbar regions form a gentle curve, concave ventrally. The promontory is more pronounced than in the horse, especially in subjects in which the sacrum is inclined upward behind. Another promontory occurs at the junction of the sacrum and first coccygeal vertebræ. Length: The following table gives the lengths of the regions of a shorthorn cow of medium size: