Boyer diss 2009 1046..

astragalus and calcaneum was highly mobile and would permit a substantial degree of
inversion and eversion, as required in an arboreal setting where substrates may occur at
random orientations and descent of large tree trunks is often necessary, requiring hind
foot reversal. The mid-tarsal joint was also identified as a point of axial mobility and
mobility in plantar- and dorsiflexion.
Szalay et al. (1975) were the first to provide substantial descriptions, figures, and
analysis for P. tricuspidens material from the Cernay collection listed by Russell (1964).
They also figured (p. 140, fig. 1) additional vertebral specimens of N. gidleyi (AMNH
17379), beyond those illustrated by Simpson (1935); however, these illustrations are not
faithful to the actual preserved morphology and instead represent reconstructions of
hypothetical complete, undistorted elements. They considered the anatomy of the
vertebrae to be lacking the appropriate comparative context and thus uninformative for
phylogenetic or functional considerations. They figured several humeri including
MNHN BR-3-L (p. 141, fig. 2; p. 143, fig. 4) and a reconstruction based on MNHN BR-
3-L, and BR-4-L (p.144, fig. 5). Szalay et al. also considered morphology of N. gidleyi
and P. walbeckensis in their discussions of humeral morphology. They concluded that
the spherical, rather than cylindrical capitulum rendered Plesiadapis and euprimates
unusually similar. Otherwise, they noted that the plesiadapid humeri were more similar
to those of arctocyonids than to those of Paleocene “insectivorans.” They figured ulnae
on pages 141-142 (figs. 2, 3). No numbers were given but I have determined that the four
ulnae in these figures, from left to right in their figure, correspond to MNHN BR-7-L,
MNHN R 452, MNHN R 1521, and MNHN R 443. Szalay et al. also illustrated a
reconstruction of a complete (minus the styloid process) and undistorted ulna based on
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