5i8 M. G. MEHL 



filled crack. From the center of the margin of the supra-acetabular 

 flange a strong ridge runs up and back in a regular curve. Below, 

 this ridge is about 20 mm. in width from which it gradually 

 narrows till it becomes confluent with the upper posterior margin 

 of the ilium. The upper posterior process is broken away, but the 

 indications are that it was a thin, platelike process with rounded 

 border, separated from the lower posterior process by a deep sinus. 

 The upper anterior process is irregular in shape, extending forward 

 in a regularly expanding spatulate form. A marked ridge extends 

 along its outer surface from the supra-acetabular flange, becoming 

 fainter anteriorly and finally confluent with the upper anterior 

 border. The process makes up nearly half of the total length of 

 the ilium, the greatest length of which is 250 mm. The lower 

 anterior projection of the ilium has a somewhat antero-posterior 

 elongated, convex face for the articulation of the pubis. The 

 articular face for the ischium, the lower posterior process, is some- 

 what larger, triangular in outline and nearly flat. These two 

 articular faces are separated by the thin, apparently complete 

 lower border of the acetabulum, strongly suggesting a perforate 

 acetabulum, as in the dinosaurs. 



Of the dorsal vertebrae but two are sufficiently well preserved 

 to be of use in description. They probably represent the anterior 

 thoracics inasmuch as they show an early stage in the transition 

 of capitular facet from the anterior face of the centrum to the 

 neural arch. The description of one of these will suffice as they 

 show essentially the same features. 



The centrum is spool-shaped, moderately biconcave, and very 

 much constricted laterally between the articular faces. This has 

 probably been greatly accentuated by pressure. The articular 

 faces are oval in outline, about 32 mm. wide and 39 mm. high. 

 The centrum is 54 mm. long and was probably 15 mm. wide at the 

 center in an uncrushed condition. The neural arch is high and 

 delicately constructed. The diapophysis is a thin horizontal 

 plate confluent anteriorly with the articular face of the zygapophysis 

 and gradually expanding posteriorly. At its posterior extremity 

 it suddenly thickens below for the tubercular facet which is separ- 

 ated from the posterior zygapophysis by a deep, rounded sinus. 



