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Boyer diss 2009 1046..

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However, they indicate that Beard’s work on N. intermedius revealed MNHN R 5305 to<br />

be a MC II. The most straightforward evidence contradicting Beard (1989, 1990) and<br />

Godinot and Beard’s (1991) final interpretation is the description and illustrated<br />

documentation of metacarpal articulations preserved in a skeleton of the micromomyid<br />

plesiadapiform Dryomomys szalayi in Bloch and <strong>Boyer</strong> (2007). The metacarpal<br />

irrefutably identified as MC V of D. szalayi based on these preserved articulations is<br />

illustrated in <strong>Boyer</strong> and Bloch (2008: p. 253, fig. 11.15). It is nearly identical to the<br />

bones identified as MC II’s previously.<br />

The “set 1” MC V (Fig. 4.14E) proximal end is distinct in having a hamate facet<br />

that is dorsoventrally convex with a large amount of its surface facing dorsally relative to<br />

the shaft. The hamate facet has a surface area of 6 mm 2 . The radial side facet of the<br />

proximal end faces slightly proximally as it arcs from the dorsal aspect of the bone to the<br />

ventral aspect. Taken as a whole, this arcing, proximally-facing facet is slightly convex.<br />

This convexity matches the concavity on the ulnar facet of MC IV. The ulnar side of MC<br />

V does not appear to have any distinctive facets, although Beard (1989, 1990) described<br />

and illustrated it as having an articulation with MC III in N. intermedius USNM 442229.<br />

The “set 1” MC V shaft narrows distal to the facets of the proximal end and then<br />

broadens dramatically as it approaches the distal end. More specifically, this MC V is<br />

distinctive among other metacarpals and the “set 2” MC V in that the ulnar margin of the<br />

distal end of the shaft flares much more than the radial margin. The asymmetry of the<br />

head of MC V is similar to that of MC IV in being opposite from the asymmetry of MC<br />

II’s and III’s. The asymmetry of the head of MC V differs from that in MC IV in being<br />

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