[parks] 



CENTROSARUS APERTUS 



61 



The only feature worthy of note is that the axis does not seem to 

 carry a cervical rib as in other forms. No trace of this rib was found 

 on either side although the parts are well preserved; it would be 

 premature, however, to state definitely that this element is lacking. 

 The individual features of the anterior cervicals are sufficiently 

 indicated by the accompanying figure (Plate V, Fig. 1). 



The scapula (Plate V, Figs. 3 and 4) is of the general type. The 

 only feature worthy of note is that on the internal face of the lower 

 end anteriorly at the suture with the coracoid there was found a 

 well-developed ossified tendon firmly attached and directed inwards 

 and back. The following measurements indicate the relative size of 

 this element: 



Measurements of Scapula 



The coracoids are both rather badly crushed ; they are apparently 

 firmly united with the scapulae. The measurements of the right 

 bone are as follows: Length, median, 182 mm.; length, oblique, from 

 point to supero-posterior margin, 288 mm.; length from point to 

 margin of glenoid cavity, 90 mm. 



The humerus (Plate V, Fig. 2) is massive with a heavy head 

 and stout radial crest. The bone is not well enough preserved to 

 render possible any detailed comparisons. The chief measurements 

 are as follows: 



The radius and ulna were found on the left side only. The 

 bones are very badly crushed and distorted, the olecranon process 

 of the ulna being entirely lost. The radius is 338 mm. long and has a 



