iVo.l.] COPE ON MIOCENE FAUN^ OF OEEGON. 63 



of facet for a trapezium. The anterior face of the magnum is wider than 

 long, and is divided into three planes. The proximal extremity is di- 

 vided into two areas by a high antero-posterior keel. The inner area is 

 the larger, and is hounded by the entire superior border of the anterior 

 face of the bone. The outer area, or the lunar facet, extends very ob- 

 liquely downwards, most so in front, where it forms the external side of 

 the magnum. It is interrupted by a large sinus, which leaves the pos- 

 terior jjortion of the face narrow and transverse. Behind it is first ? 

 fossa and then two short tuberosities, one above and external to th€ 

 other. The inferior face is undivided, and is concave antero-posteriorly, 

 and convex transversely. The unciform is the second bone of the car- 

 pus in size. Its anterior face is broader than long, and is convex trans- 

 versely. Tlie inner face has in front a large trapezoidal facet for the 

 third metacarpus, which is only separated from that of the lunar by the 

 angle. The superior face is divided, by an angular ridge nearly parallel 

 with the inner border, into two unequal faces for the lunar and cunei- 

 form. The latter is half as wide posteriorly as long, and terminates an- 

 teriorly in an obtuse angle. The distal face is undivided, but is recurved 

 postero-externally, apparently offering a narrow facet for the fifth meta- 

 carpus. This face nearly meets the cuneiform face posteriorly. Behind 

 both the unciform is produced into a decurved, subconic tuberosity. 



Measurements of the Carpus* 



M. 



0.066 



0.048 



antero-posterior 0.048 



transverse 0.030 



T^. ^ ^ , . , ( antero-posterior 



Diameter of scaplioid. -- s , . %. 



c longitudinal 



Diameter of i)roximal face of scaplioid , . . 



-p.- . ^ T J. 1 J? ^ 1 -n ^antero-posterior 0.048 



Diameter of distal face of scaphoid < ^ 



c transverse 0.023 



c, c anteriorly 0.047 



Diameter of proximal face of lunar < " ^ at middle 0.032 



( longitudinal 0.053 



Diameter of anterior face of hmar longitudinal 0.048 



( transverse 0.032 



Diameter of cuneiform 5 antero-posterior, obKque 0.059 



^ transverse, behind 0.040 



r^. . ^ . ,n J, .n c antero-posterior 0.040 



Diameter oi proximal lace oi cuneiionn < , n r, . . 



'■ ^transverse 0.044 



T,. , n .. . . . . .r. f antero-posterior 0.040 



Diameter of distal face of cuneiform < , „ ^.,1 



^ transverse 0.031 



Length of trapezoides 0.027 



Diameter of proximal face of trapezoides... \ antero-posterior 0.029 



(. transverse.... 0.016 



Diameter of distal end of trapezoides \ antero-posterior 0.020 



( transverse 0.010 



r ,. , c anteriorlv 0.029 



Diameter of magnum \ l-^-^^^-^^ \ externally 0.040 



" transverse, posteriorly 0.047 



^ antero-posteriorly, outer side 0.055 



* These measurements are alwaj s the greatest, and are axial, or in straight lines. 



