115 



this facet appears thus to occupy only the middle of the posterior surface, 

 and to be surrounded by a broad rough margin. This surface is not 

 placed at right angles to the long axis of the phalanx, but slopes from 

 above downwards and forwards at a very acute angle with the upper sur- 

 face, so that the apex of the phalanx points almost directly downwards ; 

 the inferior boundary of the posterior surface forms a rough ridge, sepa- 

 rated by a smooth narrow concavity from the anterior border of the 

 phalanx : the superior sloping surface is slightly convex, and deeply 

 pitted and sculptured with vascular grooves and impressions, 



Presented by Sir TVoodbine Parish, K. H. 



536. The middle phalanx of the third toe. This phalanx is more square- 

 shaped and broader than that of the second ; it has the same general 

 compressed form, with nearly flat articular surfaces, but being narrower 

 above, it resembles an inverted wedge : it is also notched, but less deeply, 

 below, and has an articular facet for a sesamoid bone on each side of the 

 notch. Presented by Sir Woodbine Parish, K.H. 



537- The ungual phalanx of the third toe. This is broader but shorter than 

 the preceding, and is of a more symmetrical figure : the lower margin of 

 its posterior surface forms a broader ridge, and the articular surface is a 

 little more convex ; but the resemblance is otherwise very close. 



Presented by Sir TVoodbine Parish, K.H. 



538. The middle phalanx of the fourth toe. 



Presented by Sir TVoodbine Parish, K.H. 



539. The ungual phalanx of the fourth toe. This bone has the same general 



form as the preceding, but is smaller ; like the last phalanx of the second 

 toe, it is unsymmetrical, but from a different modification : in the second 

 toe the inner margin is rounded off towards the outer one, in the fourth 

 toe the outer margin is rounded off towards the inner one. 



Presented by Sir TVoodbine Parish, K. H. 



540. The ungual phalanx of the fifth toe. 



Presented by Sir TVoodbine Parish, K.H. 



In the Glyptodon the hind foot appears to have been expressly modi- 



&2 



