YLJNXIAN ( QUYAN RIVER MOUTH) 539
Part of frontal is relatively undistorted, including
glabellar and L supraorbital regions. In profile, frontal
rises fairly steeply just behind thick glabellar and me-
dial supraorbital regions. Postglabellar region very shal-
lowly concave. Posttoral region slightly convex.
Although the obviously voluminous braincase has been
compressed s/i, parts of posterior R parietal and central
occipital regions are preserved relatively intact. As seen
in profile, parietal is low posteriorly, with a gentle, mild
curve that continues into occipital plane. Occipital
plane forms a blunt rounded angle with the short upper
portion of the nuchal plane, which is angled inward
slightly. Larger lower portion of nuchal plane is rather
horizontal. Seen from rear, appears that occipital was
extremely broad and occipital plane rather short s/i.
Lateral wall of braincase was fairly high and relatively
vertical (judging from R). Viewed from above, L me-
dial portion of supraorbital region retreats moderately
strongly from glabella, with which it makes broad an-
gle; as the supraorbital region sweeps back from
glabella, its surface is slightly concave.
As seen on the L, medial portion of supraorbital re-
gion anteriorly flat, with blunt superior margin. It
appears that the fairly tall s/i brow would have twisted
up, back, and laterally (better seen on L). Supraorbital
notch large and shallow, lying very medially. Very wide
interorbital region was probably quite broad superiorly
and tapered inferiorly, while remaining absolutely broad.
Glabella wide and quite prominent, and slightly sunken
in midline; did not overhang nasion much. Appears
that orbital roofs were minimally concave. Although
somewhat compressed, preserved medial, mediosu-
perior, inferior, and inferolateral margins of L orbit
suggest a rectangular rather than rounded orbital con-
formation. Supraorbital torus not continuous across
glabella. Judging from both sides, infraorbital region was
tall s/i and anteriorly facing.
Distally broken nasal bones flexed forward quite
strongly below the subglabellar indentation (were
probably quite horizontal distally, although not very
long). Judging from what appears to be the location of
the frontonasal suture, nasal bones were quite broad
superiorly and may have been parallel sided. Nasal
aperture was apparently very broad, very tall, and
somewhat protrusive (judging by obliquely oriented
frontal processes). L inferolateral portion of nasal aper-
ture is preserved; margin is rounded instead of the
bearing a continuation of the lateral nasal crest. Base of
anterior nasal spine preserved and quite massive. Large
infraorbital foramina lie well below blunt inferior
orbital margin, opening into a slight depression (not a
canine fossa). As seen on the L, thick anterior root of
zygomatic arch lies somewhat above region between
Ml and 2; from front, the root takes a strong lateral
curve. Profile of infraorbital plane oriented gently
obliquely back from top to bottom. Maxillary sinus ex-
tended to some extent laterally, at least to level of lat-
eral margin of orbit. As seen on the L, it appears that
the nasoalveolar clivus was quite long and possibly flat
across, bulging in the region of canine root; it also
flows smoothly from face into floor of nasal cavity.
As seen on the L, posterior surface of frontal
process of zygoma is flat, quite wide m/l, and rather
posteriorly facing, suggesting some degree of postorbital
constriction. Small portion of L temporal line is pre-
served high up at the superolateral margin of supraor-
bital torus. Temporal fossa apparently flowed smoothly
into infratemporal region without distinction. Appears
also that anterior squamosal does not corner into tem-
poral fossa. As indicated on both sides, posterior root of
zygomatic arch is long and angled laterally and forward.
Squamosal was relatively short, with a strong superior
curve. Petromastoid region rather large. As seen on the
L, a low suprameatal crest swells into the thicker but
still low and horizontal suprameatal crest.
Articular fossae deep, long a/p, and very wide
m/l; as seen on the R, fossa is somewhat closed off
medially by a low, blunt medial articular (entoglenoid)
tubercle. As better seen on the R, posterior wall of ar-
ticular fossa is formed by the petrosal and angled
backward quite strongly. More vertical anterior wall of
articular fossa flows smoothly onto sphenotemporal
bone in front (thus no articular eminence). On both
sides, it appears that auditory meatus did not extend
laterally to posterior root of zygomatic arch; also, that
there was a basally thick vaginal process running all
the way along long axis of ectotympanic tube. Ecto-
tympanic tube contacts base of mastoid process later-
ally. As preserved better on the L, mastoid process is
quite massive at its base, swelling out from the lateral
wall of braincase. Maximum cranial breadth occurs at
this point. Apex of mastoid process long a/p, broadly
convex, and somewhat obliquely oriented; projects
moderately below cranial base. Mastoid notch broad
m/l and very deep; probably terminates posteriorly in
a small, shallow digastric fossa. Medial to mastoid
notch, bone swells significantly into a long, raised area
in what appears to be the region of the occipitomas-
toid suture (not itself visible); no sign of a Waldeyer’s
crest medial to this ridge. Nuchal plane appears to