XO. 14 A NEW SAUROPOD DINOSAUR — GILMORE 3 



ened and rounded. The posterior border, however, continues down- 

 ward as a fairly sharp edge to the downward swing of this border to 

 form the glenoid socket where the bone rapidly thickens transversely. 

 The spine or ridge on the lower external surface extends from the 

 base of the shaft' in an anterior direction to the anterior-superior 

 border, and at right angles to the longitudinal axis of the bone. This 

 ridge is not greatly elevated except that on the side toward the cora- 

 coidal border the bone is rapidly and deeply excavated, forming a 

 muscle fossa of great extent. On the upper side of this ridge the 

 surface of the bone slopes off gradually to the border, there being 

 no excavation or superior fossa such as is found in so many Sauropod 

 scapulae. 



Measurements ^ ^. 



Centimeters 



Greatest length of scapula (as preserved) 155 



" " " " (estimated) 170 



Greatest breadth of superior end 45 



Least breadth of shaft 29 



Greatest breadth inferior (oblique) 82 



Thickness of shaft at center 29 



Ischium. — A large bone found in the same horizon but sortie 200 

 feet distant from the scapula described above is identified as the right 

 ischium of a Sauropod dinosaur. This bone differs so from other 

 Sauropod ischia that its true nature was determined with difficulty. 

 That it pertains to a member of the Sauropoda is indicated by its 

 large size and also by its general resemblance, though dift'ering 

 markedly from any described form. It is characterized by its extreme 

 shortness, and especially by the lack of the long, slender posterior 

 extension so characteristic of other Sauropod ischia. 



The proximal portion is nearly complete, lacking only a small por- 

 tion of the sharp inner edge of the acetabular border. The distal end, 

 though not perfect, apparently lacks but little of being complete. 

 Likewise the thin inner border below the articulation for the pubis 

 is slightly imperfect. Except for the missing portions mentioned, 

 the bone is in a remarkably fine state of preservation. 



The expanded proximal end is unusual, not so much because of 

 its great antero-posterior extent, but on account of the great dorso- 

 ventral diameter, and especially the great length of the pubic articula- 

 tion which extends distalward more than one-half the total length of 

 the bone. Below the pubic articulation the inner border presents a 

 thin, sharp edge, and the flattened distal portion gradually diminishes 

 in width to the distal end. This end is apparently without distal 



