109 



dental canal : the second socket shows, by the two prominent vertical 

 ridges on its anterior and posterior walls, that the tooth which it con- 

 tained had the fluted form characteristic of the genus : the third socket, 

 which is the most complete, differs from the preceding in a slight in- 

 crease of size, and it shows that the tooth was implanted by an undivided 

 base of considerable length, and of the same size and form as the ex- 

 posed part or crown. Presented by Sir Woodbine Parish, K.H. 



518. The distal portion of the left humerus of the Glyptodon clavipes, in which 



both the outer and inner supra-condyloid plates are broken off; but 

 they seem to have been relatively less developed than in the Mylodon 

 robustus. The anterior and posterior depressions above the distal arti- 

 cular surface are deeper ; there is no trace of a perforation above the 

 internal condyle : the radial division of the trochlea is less convex than 

 in the recent Armadillo. The twist of the humerus is strongly marked ; 

 the base of the strong deltoid trochanter is discernible at the fractured 

 extremity of the bone ; but on the opposite side there is a rugged 

 raised surface for a muscular insertion, of which the analogue is not 

 visible in the Armadillos. There is a medullary cavity in the shaft. 



Presented by Sir Woodbine Parish, K.H. 



519. The left radius of the Glyptodon clavipes: the proximal articular surface 



has the form of a transverse oval, which is concave from before back- 

 wards and convex from side to side : in this respect it agrees with the 

 Armadillos and differs from the corresponding bone in the Megatherioid 

 animals. The muscular ridges and depressions are well-marked, but less 

 strongly than in the Mylodon. The bone assumes somewhat of a 

 trihedral figure towards its distal end ; the anterior ridge is produced 

 below the distal articulation in the form of an obtuse, sub-compressed 

 process ; the posterior ridge terminates in a broad rugged process ; the 

 radial, which in the prone position of the bone becomes the inner side 

 of the distal extremity, is much produced ; the distal articular concavity 

 is formed by an oblique excavation leading downwards from the posterior 

 towards the anterior margin of the distal end ; the articular surface 



