I n a box of fossils sent to Sir R. I. Murchison, Bart., by Mr. Alfred Brown of Aliwal North, South Africa, and submitted to me for examination and determination, I found certain fragmentary large reptilian bones, to which a very considerable interest attaches. The most important of these are two femora, a right and a left. The articular ends of both of these bones are wanting; and the shaft of the left is far less complete than that of the right, to which the following remarks more particularly apply. It is broken into four pieces; but these, when carefully fitted together, have a total length of 25·5 inches; and it may be safely assumed that the length of the entire femur exceeded 30 inches, as its distal extremity is only beginning to widen for the condyles. At 20·5 inches from the proximal end, the transverse diameter of the shaft is 5·1 inches, the antero-posterior diameter 4·2 inches. The contour of the transverse section at this point is a transversely elongated oval, the posterior face being so much more flattened than the anterior as to make it almost semilunar. Viewed sideways, the shaft of the bone is, for the greater part of its length, nearly straight, though its dorsal contour is a little convex. But towards the proximal end it becomes widened and flattened from above downwards, while, at the same time, its longitudinal contour becomes concave above and convex below. In its dorsal, or upper, aspect also, the greater part