150 H. G. SEELEY ON THE FEJIUR OF CEYPTOSATJRTTS EUMERUS, 



one might infer that the ilia were not directed upward and inward, 

 converging as among birds, but rather outward as among reptiles, 

 or upward as among some reptiles and some mammals. This condi- 

 tion may also be infered from the ordinary Dinosaurian sacrum, 

 which, widened with transverse processes or bones, is more easily 

 harmonized with that of a mammal or a reptile than with the sacrum 

 of birds. 



The great trochanter is a mastiform process (figs. 1 & 3, a) partly 

 separated from the anterior side of the bone by a deep narrow groove ; 

 in front it is rounded and does not extend so far proximally by 

 | inch as the articular surface. The groove or slit is nearly parallel 

 to the posterior side of the bone ; it is 1J inch deep on the outer 

 side of the bone, but not more than | inch deep on its front aspect. 

 Between this trochanter and the ball of the femoral articulation the 

 bone is deeply concave laterally (fig. 3). A badly defined ridge 

 extends 8 inches distally from the trochanter, along the front of 

 the bone, inclining obliquely inward so as to make a prominence 

 in the middle of the front of the shaft just below the point of its 

 least diameter from within outward, which measures about 2 inches. 

 Below the trochanter the bone becomes slightly narrower from back 

 to front, and about halfway down the shaft is constricted to If 

 inch, and thence thickens slightly to the bend in the shaft 8 inches 

 from the proximal end. The outer side of the bone becomes less 

 flattened in descending the shaft, and more convex from front to 

 back. The back of the bone is on the whole flattened. 



The longitudinal outlines of the bone are externally gently con- 

 cave, on the inner side much more concave ; while anteriorly the 

 outline is bent in the distal third and has its proximal part subpa- 

 rallel to the posterior outline, though below the bend the outlines 

 diverge towards the distal articulation. Below the bend the form 

 of the anterior area is roughly triangular, since the outline widens 

 from the bend towards the distal face, where it measures 4 to 

 4| inches from side to side. The inner surface is flattened distally 

 and looks inward and somewhat forward, rounding into the front 

 of the bone. The outer surface is narrow distally and rounds ob- 

 liquely and convexly into the front. 



The characteristic Dinosaurian trochanter on the middle of the 

 shaft is removed by fracture, but was placed entirely on the posterior 

 aspect of the bone, about 4J inches from the proximal end and b\ 

 inches from the distal end (figs. 1, 2 c). Its fractured base, which 

 measures 2J inches in length and 1 inch in width, appears to indi- 

 cate that the trochanter was directed backward : it divides the inner 

 outline of the shaft into two concavities. 



The shaft is triangular at the distal end (fig. 4), as at the proxi- 

 mal end, only the wide side distally is the inner side, and the less 

 rapidly and less regularly converging sides form an external angle. 

 The distal articulation forms a right angle with the axis of the 

 shaft. The articular surface is convex from front to back, while 

 from within outward it is very slightly curved, being concave in the 

 middle and convex on each side externally. It has two principal 



