82 PKOF. H. G. SEELEY ON THE 



pubis. It is directed downward and backward, from in front of 

 the acetabulum, from which it is separated by a narrow notchi 

 Only about 1 J inch of its length is preserved, but this shows it to be 

 a vertically compressed, slightly oblique rib-like process, sub-ovate 

 in section, being about 1-^ inch deep by -^jj inch wide. The notch 

 which divides it from the acetabulum is much narrower than in 

 Iguanodon ; and the process is not prolonged on to the inner 

 surface of the pre-acetabular part of the bone with the same con- 

 vexity of surface as in Iguanodon^\iVii is flattened. in the way shown 

 in fig. 1, facing this page. 



The articular surface on the pubis, for the ilium is situate at the 

 upper hinder angle of the bone, above the acetabulum, which it 

 meets at about a right angle. It is oblique to the superior contour, 

 being inclined backward ; is subtriangular in form, rugose, convex, 

 about 2 inches wide and nearly as deep ; it manifestly fitted on 

 to the descending pubic process of the ilium, though, owing to com- 

 pression of the shield, it does not now make a close union. 



The acetabular surface of the pubis is below and behind its iliac 

 articulation. It is oblong, 3| inches in length, smoothly concave as 

 it extends downward and backward, is inclined somewhat obliquely 

 outward, and terminates inferiorly in a defined margin, below which 

 is an oblique compressed rounded lip, which presumably connected 

 with the ischium. The lateral acetabular margins are subparallel, 

 the external side being flattened; and the internal side, which 

 extends about 1 inch farther backward, is more concave in the 

 vertical direction. The transverse measurement below the iliac 

 articulation is under 2 inches, whilst inferiorly, towards what I 

 regard as the ischiac surface, it exceeds 1 inch. 



The ischiac articulation, when seen from behind, is small and 

 semi-ovate, being convex below ; it is oblique, so that its depth 

 is twice as much on the inner as on the outer border. It is 

 convexly rounded, both from side to side, and from the acetabular 

 margin downward. In no other specimen have I seen this surface 

 so well preserved. 



The anterior blade of the pubis is directed forward and down- 

 ward from the acetabulum, and slightly outward. It is relatively 

 short when compared with the pre-acetabular part of the bone in 

 Iguanodon, Camptosaurus, and allied genera, with which it may be 

 compared on account of the similarity in form and condition of the 

 base of the posterior element of the pubis. It does not show the 

 anterior antero-posterior widening seen in Iguanodon nor the forward 

 curve at its extremity figured in Camptosaurus, It is obviously 

 shorter and relatively deeper than the same element in Stegosaurus, 

 which has the post-acetabular part of the bone almost as wide as the 

 pre-acetabular part. This blade is oblong in form, compressed, and 

 becomes thinner as it extends forward. Its length, measured from 

 the external acetabular border, is 6| inches ; from the hiudermost 

 posterior border of the acetabulum the length is 8| inches. The 

 depth of the bone is about 5 inches in the articular region, 4 

 inches in the middle in front of the post-acetabular element, and 



