Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/515

 the inner surface is less convex transversely than the outer, and bears a deep longitudinal groove. The buccal surface is longitudinally flat, and it rises gently towards its inner border, which makes it slightly hollow transversely. The outer surface of both fragments is smooth ; it has a close grain, and a fine longitudinal striation.

Dimensions of the Anterior Extremity of the Upper Maxilla.

inches.

Antero-posterior diameter of symphysis 1.8

Maximum vertical depth of symphysis 2.3

Length of fragment of intermaxilla 4

Diameter of first and second alveoli in right intermaxilla 1.1

Width of nostril at level of its floor at posterior surface of fragment 1.8

Width of nostril at angle where the inner and upper surfaces of intermaxilla meet 1.5

Maximum width of nostril at angle where upper and outer surfaces meet 3.1

Vertical depth of intermaxilla at posterior surface of fragment 1.9

Transverse diameter of intermaxilla at junction of upper and inner surfaces 1.3

Do. do. at floor of nostril 1.65

Max. vert, depth of nostril from its floor to meeting of upper and outer surfaces of intermaxilla 0.95

Breadth of snout just behind symphysis 3

Lower Jaw. — In the British Museum there is now, stripped of its matrix, in continuous fragments, which have been cleverly joined by Mr. Davies, a nearly complete right ramus, including the entire non- tooth-bearing part, measuring 30 inches from its posterior extremity to the hindermost visible tooth *, with 4 inches of the toothbearing part. Viewed from above, the dentary part, with 4 inches of the ramus behind it, appears to be nearly straight, and from this point the ramus curves outwards nearly to its posterior extremity, where it becomes slightly inflected. When the straight, toothed part is placed horizontally, the ramus behind it is observed to have a large upward curve. The upper border of the jaw, traced from behind forwards, exhibits first a gently inclined, slightly longitudinally hollowed and transversely flat postarticular surface, 2.7 inches long, separated by a transverse ridge from a longitudinally concave articular surface of nearly equal length, which looks forwards and upwards. From this the border declines gently for about 5 inches,

tooth, exposing four more alveoli, which, with two, for which there is ample space in an intermediate fragment on which the distal end of the femur lies, make six, or perhaps seven, teeth behind the point where the symphysis probably begins, and lessens the length of the non-tooth-bearing ramus to between 22 and 23 inches.
 * The upper surface has been more recently cleared of the matrix behind the