Boyer diss 2009 1046..

previous authors also do not mention a fragment of the squamosal and zygomatic sutured
together, a left anterior premaxillary piece and a fragment of the right nuchal crest. The
latter two elements are illustrated as isolated bones here. Furthermore, a fragment of the
right zygomatic bone has been removed, but was temporarily reattached for photography.
Finally the ventral part of the right ectotympanic bone was either intentionally or
accidentally removed (Bloch and Silcox, 2001). The right ectotympanic has not been
reattached because, when separated, the annular part of the ectotympanic and more of the
promontorium can be viewed and studied than would otherwise be possible. Thus, the
skull exists in five pieces; seven if both dentaries are counted. There appears to be a
substantial amount of brittle deformation inflicted on the skull. The degree to which this
distorts the true morphology was not determined previously, but is analyzed here (see
Discussion and Conclusions). The specimen is interpreted to represent a young individual
because, although the adult dentition was completely erupted, the teeth are almost
completely unworn and most long bone epiphyses remained unfused to diaphyses.
Nasal.— The nasals have been shifted away from the bones they contacted;
thus the shape of these bones is apparent, but not which bones they contacted (Fig. 3.1).
Their mediolateral width is fairly constant from anterior to posterior (anterior unilateral
width = 4.9 mm, posterior unilateral width = 4.5 mm), possibly with a slight midpoint
constriction (Fig. 3.1). Due to breakage, shifting and crushing of bone, it is not possible
to determine whether the nasals would have contacted the maxillae as well as the
premaxillae (Fig. 3.1: 1) and frontals (they do not contact the maxillae in other known
plesiadapids). The nasals appear to have extended posteriorly to the level of M 1 , but this
is at least partly an artifact of the skull’s deformation.
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