Boyer diss 2009 1046..

Szalay and Decker (1974) regarding the ankle joint. All of the material mentioned in
Szalay et al. (1975) was observed, photographed, and measured in the course of the
current work.
Gingerich (1976) contributed to knowledge on the plesiadapid postcranium by
providing photographs and measurements of limb bones of the specimen of P. insignis
from Menat (p. 35, table 6; p. 84, fig. 36 and table 12; pls. 11-12). Furthermore, he
mentioned the existence of a distal humerus of Platychoerops (UCMP 103829). He
remeasured the postcranial elements of P. tricuspidens depicted in Simons (1964) and
came up with a slightly different set of brachial (95), crural (100), and intermembral (88)
indices than given by Szalay (1972). However, as mentioned above, the length of the
tibia of P. tricuspidens is not actually known. He reported the same set of indices for P.
insignis as 86, 91, and 72, respectively. Gingerich was the first to extensively compare
plesiadapids to sciurid rodents, the lack of which he regarded as a shortcoming of
previous treatments by Gregory (1920), Simpson (1935) and Szalay et al. (1975). He
concluded that the limb proportions were similar to those of terrestrial sciurids and
Marmota. Furthermore, he interpreted the robustness of the limbs as more consistent
with a terrestrial, rather than arboreal, habitus. His interpretation of the evidence from
the humerus, ulna, and radius of N. gidleyi (AMNH 17379) added support to this
conclusion. Specifically, the large teres major tuberosity on the humerus was noted to be
consistent with a digging habitus. Furthermore, Gingerich saw the morphology of the
ulna and radius as having the capacity for only limited pronation and supination. He
noted that the distal humeri of Plesiadapis (as figured by Teilhard de Chardin, 1922) and
Platychoerops (UCMP 103829) differ from that of N. gidleyi in having more expanded
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