CONDYLARTHKA. 453 



Mesonyx, which a good deal resemble them, have the unguiculate character, 

 although not very pronounced. Tlie fifth metacarpal is just half the length 

 of the third. In its proportions it reverses those of the corresponding meta- 

 tarsal, for the proximal extremity is only one-half the width of the distal. 

 In the metatarsal the proximal is the wider extremity. The proximal facet 

 of the metacarpal is sublenticular, and descends anteriorly, the anterior 

 apex being at the inner side. Opposite the latter, on the external side of the 

 shaft, is a low tuberosity. The distal extremity is a little oblique, but the 

 posterior extremity of the heel is nearly median (though it commences at 

 the inner side), and the lateral distal faces are in the same plane. The 

 internal side of the proximal extremity of the second metacarpal is rough- 

 ened with two longitudinal fossae, bounded by bands of the surface, of which 

 the anterior is flattened. 



Measurements of metacarpus. 



M. 

 flongitndiual 065 



mediau transverse 014 



Diameters of second ■( 



I distal ^ anteroposterior 014 



t I transverse 015 



'longitudinal 072 



proximal ^ ''°*'"°P°"f*'"°' ^" 



Diameters of third <! ,. 'transverse 012 



median transverse 014 



distal ^ anterojiosterior 013 



Diameters of fourth < 



transverse 013 



longitudinal 036 



. < anteroposterior 013 



I transverse 007 



median transverse 010 



distal ^ anteroposterior 010 



transverse 016 



'longitudinal 060 



.015 

 .011 



median transverse 012 



,. . , J anteroposterior 013 



proximal \ anteroposterior 

 < traus\'erse 



Diameters of fifth ■ 



r 



transverse Oil 



The proximal and distal measurements given above are those of the 

 articular surfaces. 



There is nothing exceptional about the phalanges. They are all 

 depressed, those of the first and fifth digits the least so. The distal articu- 

 lar facets of the first phalanges are not much emarginate nor reverted, and 

 those of the second are more reverted, and not in the least emarginate. 



