484 AsI;\, EASTERN AND CENTRAL
eminence, development of suprameatal and supramas-
toid crests and of occipital tori, sagittal “keeling,” depth
of sigmoid sinus, and distinctiveness of transverse sinus.
There is, on the other hand, greater consistency among
the specimens in development of low, very wide crania
(S10 being relatively tall), swollen bregmatic regions
with paired depressions behind, small, ovoid auditory
meati, long and low squamosals, shallow parietal not-
ches, deep articular fossae bounded medially by thicken-
ings of the temporal bone (not tubercles), grooves for
the superior petrous sinus, and closure of the subarcuate
fossae; and no contact between the ectotympanic tube
and the mastoid process, no cornering of the anterior
squamosal or alisphenoid (no infratemporal fossa), no
elevation of an articular eminence, no segmentation and
little interdigitation of cranial vault sutures, and failure
of the frontal lobes to extend far over the orbital cones.
Sungirun 2. Calotte, partly reconstructed, missing
R supraorbital region.
Small braincase with relatively thick bone. Profile
long and not very tall, apparently with supraorbital
and occipital distensions in same plane (when frontal
crest oriented vertically). Preserved lateral half of L
supraorbital region thinner s/i laterally than medially,
with anterior border smoothly rolled. Break in mid-
line of this region reveals solid bone (no sinus), also a
profile in which height of bone increases somewhat
from anterior border of orbit to posterior extent of
orbital roof (i.e., orbital cones lie almost entirely in
front of frontal lobes). Frontal plane rises level with
anterior extremity of frontal lobes, paralleling contour
of frontal lobes internally. Frontal contour in coronal
plane forms a smooth curve from side to side. There is
breakage more anteriorly, but keeling is not detectable
in region of bregma, which is broadly swollen and
emphasized posteriorly by twinned depressions on
either side of sagittal suture. Posteriorly, coronal con-
tour of cranium becomes flatter and broader as skull
expands to maximum width near region of parietal
notch. Viewed from above, greatest postorbital con-
striction is posttoral but not pronounced (lateral flare
of orbit, while distinct, is not extraordinary). On the
L, a low, roughened temporal line emerges from lat-
eral extremity of zygomatic process of frontal and runs
anteriorly before curving back to arc gently to poste-
rior flexure of cranium. Temporal lines and bone
lateral to them bulge only slightly.
Viewed from behind, cranium is very broad and
almost flat superiorly; side walls above asterion titinward slightly. Below parietal notches, temporal bones
angle inward more strongly. A distinct, blunt, V-
shaped, horizontally oriented angle between occipital
and nuchal planes carries completely across back of
braincase from parietal notch to parietal notch.
Throughout most of its length, this angle is not “torus-
like,’’ since only across the middle part of the occipital
is there a shallow sulcus above that emphasizes the an-
gle below it; inferiorly, no sulcus at all below the angle.
Nuchal plane relatively flat across and unadorned, ex-
cept for a low bulge corresponding to R cerebellar lobe.
Squamous portions of temporals appear long and
fairly low. Region of parietal notch tilts in slightly
when viewed from back; notch itself is quite shallow.
Anteriorly, contour of squamosal flows imperceptibly
into contour of alisphenoid. Bone along alisphenoid is
only very gently convex from top to bottom, (i.e., no
infratemporal fossa). Preserved posterior root of L zy-
gomatic arch projects anterolaterally from anterior
part of articular fossa; would probably have supported
a somewhat flaring zygomatic arch (thus temporal
fossa was probably both long alp and wide m/l, at
least anteriorly). Shelf above posterior root small, tri-
angular, tilted downward; lies entirely in front of
small, ovoid auditory meatus.
Especially as seen on the L, articular fossae were
deep, more constricted a/p laterally than medially,
bounded less by a distinct medial articular tubercle
than by a lateral thickening of medial wall of fossa.
Surface of articular eminence not elevated; runs
straight forward into temporal fossa. Bone of ecto-
tympanic tube thick; tube was probably incompletely
ossified laterally on both sides. On better (but still
very poorly) preserved L, vaginal process appears to
have reached its peak quite medially, more or less level
with medial wall of articular fossa. Articular fossae
and ectotympanic tubes are laterally oriented. Speci-
men is asymmetrical in respect of suprameatal and
supramastoid crests. L suprameatal crest undeveloped
and supramastoid crest modestly swollen. Both R
crests rather stout and confluent with one another. On
both sides, supramastoid crests sweep upward and
back, reaching greatest expression at region of parietal
notch. Mastoid region damaged on both sides; from
the R, it seems there was no distinct projecting mas-
toid process; instead, bilaterally below supramastoid
crest, a thickened area follows the inwardly sloping
contour of bone to behind the ectotympanic tube,
which it encloses posteriorly. This thickening of bone
would not have been as downwardly projecting as the