360 University of Kansas Geological Survey. 



Coracoid. 



The coracoid is a remarkably short bone for so large a turtle. 

 The single bone preserved, of the right side, lies immediately 

 above the proscapula and below the carapace. Its articular 

 end is thickened, with a thinner expansion for articulation with 

 the scapula. The scapular border is deeply concave, the distal 

 extremity thin and moderately expanded. The outer border, 

 except proximally, is wanting, but, from the thinness of the 

 border at the extremity, it appears to have been nearly straight. 



Length 100 mm. 



Width at proximal end 35 



Width of shaft (approximately) 18-20 



Humerus. 



The humerus is a very large, flat bone, intermediate in some 

 respects between that of Protostcga and that of Chelone, but with 

 a narrower shaft than in either. Both bones were originally 

 present, but unfortunately the left one is represented only by 

 fragments. The distal end is shaped very much as in Chelone, 

 save, as already stated, that it is more constricted above, below 

 the radial process. The radial process is even larger than in 

 Protostega, though not reaching as far down the bone. The ul- 

 nar process, on the other hand, is even more elongated than in 

 Chelone, and is apparently even longer than I have represented 

 it in the drawing. The bone is in all respects the humerus of a 

 sea turtle. 



Length from top of articular surface 202 mm. 



Extreme length, about 260 



Greatest diameter of a scapular articular surface 44 



Least width of shaft 40 



Width through lower part of radial crest 67 



Greatest width distally 80 



Thickness of shaft 17 



Radius. 



Lying nearly in connection with the portion which is pre- 

 served of the left humerus, are the nearly complete radius and 

 a portion of the ulna. The radius has been but little com- 

 pressed, and it is in excellent preservation, save for the part 



