Boyer diss 2009 1046..

eveals that 1) the postgenoid process is broken off and missing, 2) a postglenoid foramen
is preserved and is located medial (not posterior) to the area from which the postglenoid
process would have projected (Fig. 2.2D, E: 17), and 3) there is a well-developed
entoglenoid process medial to the postglenoid foramen (Fig. 2.2E: 18). Furthermore the
glenoid is revealed to be rather flat, and anteroposteriorly longer (6.96 mm) than
mediolaterally wide (5.38 mm). The joint surface is deformed on its medial aspect where
the right M 1 or M 2 crown is pressed into it. The entoglenoid process is quite large,
projecting ventrally beyond the glenoid fossa by 1.79 mm. It is oriented longitudinally,
at roughly 90 degrees from the hypothetical orientation of the intact postglenoid process,
and slopes medially. The width of the zygomatic process of the squamosal at its base,
where it meets the glenoid, is 1.76 mm (Fig. 2.2E: 19). The length of the process, which
appears to be mainly intact, is 4.95 mm. Its maximum depth is 3.77 mm.
Alisphenoid and basisphenoid.—Neither of these elements is recognizably
preserved.
Petrosal.—The main structures in the basicranial region that are well preserved
and can, therefore, be described in detail are the promontoria of the petrosals (Figs. 2.2-
5). Two isolated petrosals of Pr. gaoi will also be described here (Figs. 2.6-7).
Accordingly, several major points regarding the morphology will be addressed. First, the
promontorium itself will be described (its shape and the presence, position, and
relationships of any grooves and foramina). Next, the morphology of the bones
surrounding the promontorium will be addressed, inasmuch as this morphology relates to
anatomical interpretations of previously mentioned promontorial features. The form,
number and position of bony processes extending from the promontorium will then be
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