Boyer diss 2009 1046..

difference makes them more like known paromomyid plesiadapiforms (Beard, 1989;
Boyer and Bloch, 2008). Thus, their attribution to Plesiadapis is questionable.
Intermediate phalanges
Description.—Seven intermediate phalanges are included in UM 87990 (Table
4.14; Fig. 4.21). Four of these are complete. As for the lateral proximal phalanges, these
elements are all generally similar except with regard to a few features that may reflect
differences between bones of the hand and foot. Previous studies (Beard, 1989; Bloch
and Boyer, 2007; Boyer and Bloch, 2008) have suggested that the manual elements are
shorter. Although only one of the intermediate phalanges identified as a manual element
can be measured for its total length (Fig. 4.21, Table 4.14), three others are complete
enough to reveal that they would have been much shorter than three others identified as
pedal elements. These shorter elements, identified as belonging to the hand, also appear
to be smaller midshaft dimensions and to have proximal ends that are proportionally
smaller in their dorsventral dimensions. Natural logarithm shape ratios constructed to
quantify these differences show that among the P. cookei sample, as well as among other
plesiadapids, the manual intermediate phalanges are probably more robust and may have
slightly shallower dorsoventral dimensions of the proximal end (have a greater SSV, and
lower BSV, respectively: Table 4.14). However, the dorsoventral dimensions of the
proximal and distal ends do not appear to consistently differentiate proximal phalanges
into manual and pedal groups (BSV and HSV: Table 4.14).
In general, the intermediate phalanges have a cylindrically concave proximal
articular surface. It is often marked by three longitudinal grooves that fit the three
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