Page:Quarterly Journal of the Geological Society of London, vol. 29.djvu/614

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PROCEEDINGS OF THE GEOLOGICAL SOCIETY.
[June 25,

which may be a lunare, and the other, from the coaptation of one of its articular surfaces, maybe the corresponding ossicle in the second row. Two metacarpals and the proximal end of a third are recognizable. Their lengths are ⋅67 and ⋅7 inch. The proximal ends are squared and stout, the diaphysis is slender, and the distal end pulley-shaped. Seven digital phalanges remain, of which three are ungual. Of the four others, the two larger are respectively ⋅3 and ⋅25 inch long, which is nearly twice their transverse diameter taken midway between the articular ends. The two smaller phalanges are ⋅5 and ⋅2 inch long; and even these, relatively to their width, are longer than corresponding phalanges in the manus of Mantell's Iguanodon. The unguals (a,b) are nearly straight, sharply pointed, and they are not depressed and flattened as those of Iguanodon, from which they also differ in the presence of a conspicuous claw-groove, which runs inside the upper surface of a slightly projecting border that separates the upper from the under surface of the phalanx.

Haunch and hind limb.—I did not recover the ilium; but three from two other individuals were strikingly like those displayed in the familiar Iguanodon-slab from Maidstone, preserved in the palæontological gallery of the British Museum. The upper border, which is rather stouter than the broad plate below it, is prolonged forwards above and beyond the acetabulum as a long, slender process, which I have not seen complete, but which, in a nearly perfect specimen, was about as long as the postacetabular part of the bone. In these three examples the lower preacetabular, or pubic process, was well marked. It was directed downwards and forwards when the axis of the ilium was placed parallel with that of the vertebral column. The ischial articular facet was a slightly swollen eminence, not deserving, any more than in Mantell's Iguanodon, to be called a process. Behind the acetabulum the lower border of the bone is directed almost horizontally backwards, and it makes a blunt angle with the upper border, which bends downwards and meets it. The postacetabular part of the broad plate, or body of the ilium, at the level of about two thirds of its depth from the upper border, is angularly inflected towards the mesial line beneath the sacrum. The inner surface is stamped, as in Iguanodon, with a sinuous impression of alternating elevations and depressions corresponding to the shape of the outer surface of the confluent sacral transverse processes. The pubes and ischia are known to me only in the Mantell-Bowerbank skeleton.

Femur.—The thigh-bone has a general resemblance to that of Iguanodon; but it may easily be distinguished from this by the form, relative size, and the position of its inner trochanter. This, when perfect, is a large triangular wing pointing downwards, and situated nearer the proximal end of the thigh-bone than in Mantell's Dinosaur. The head is subglobular, and it is borne on a distinct neck, which makes almost a right angle with the axis of the shaft. In two very perfect and undistorted examples, the proximal end of the shaft was laterally compressed in such a way that its surfaces looked outwards and inwards when the neck was supposed to be directed ver-