Boyer diss 2009 1046..

History of descriptive study of plesiadapid cranial material
Simpson (1935) provided the initial description of a plesiadapid skull and
associated dentition (AMNH 17388), now attributed to Nannodectes gidleyi (Gingerich,
1976). The specimen came from the Mason Pocket locality in late Paleocene strata of the
Nacimiento Formation, San Juan Basin, Colorado. The details Simpson provided on the
cranial anatomy are brief. No figures were provided.
Russell (1959) provided a preliminary description of a more complete plesiadapid
skull, Plesiadapis tricuspidens (MNHN CR 125), from the Berru locality near Reims in
late Paleocene strata of the Paris Basin, France. This contribution included a labeled
sketch of the skull in dorsal and ventral views, and corresponding photographs. As
summarized by Gingerich (1976), Russell described the general form of the skull,
interpreted it as preserving large premaxillae that contact the frontals, and otherwise
focused on the basicranium. Russell (1959) stated that the skull preserves a posterior
carotid canal, and that there are two subequal grooves on the promontorium for the
promontory and stapedial arteries. He also stated that the bullae appeared to have been
derived from the petrosal.
Simons (1960: fig. 1) reviewed the find of MNHN CR 125 and provided a
reconstruction of the skull in lateral view. The caption states that there is “correction for
distortion.” Simons noted the lack of a postorbital bar and relatively large antemolar
dentition as distinctive features of this Paleocene “primate,” contrasting it with
euprimates.
Russell (1964) provided the most comprehensive description of a plesiadapid
skull (P. tricuspidens, based on MNHN CR 125, 126, 966, 965; 4306) as a follow-up to
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