SAUROPTERTGIA 



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somewhat flattened ; the thick articular end, which forms 

 shortest ray, is subequally divided 

 by the articular surface for the 

 coracoid, and that for the head of 

 the humerus. 



The coracoids are chiefly re- 

 markable for their excessive ex- 

 pansion in the direction of the 

 axis of the trunk, extending from 

 the abdominal ribs forward, so as 

 to receive the entosternum, which 

 is wedged into their anterior inter- 

 space. The median borders meet 

 and unite for an extent deter- 

 mined by their degree of curvature 

 or convexity, which is always 

 slight. The coracoids unite an- 

 teriorly with the clavicles, as well 

 as with the epi sternum ; laterally 

 they articulate with the scapula, 

 combining to form the glenoid 

 cavity for the humerus. 



The episternum has the same 

 general form as the median pieces 

 of the abdominal ribs, being, like 

 those pieces, a modified haemal 

 spine, only more advanced in 

 position ; the lateral wings or 

 prolongations are broader and 

 flatter ; the median process is 

 short; a longitudinal ridge pro- 

 jects from the middle of the in- 

 ternal surface. The humerus is 

 a moderately thick and long bone, 



