Onio KIBISII 237
long a/p and only minimally swollen; in profile, their
edges do not converge strongly inferiorly (suggesting
process was long a/p throughout). When viewed from
rear, sides of processes gently arc medially. Both mas-
toid notches very deep; R much wider m/l, extending
much more posteriorly than L. Posterior margins of
both notches do not flow into digastric fossae but are
delineated by a shallow margin. Behind this margin lie
relatively large mastoid foramina on both sides. Mas-
toid notches extend anteriorly to faces of medially
placed styloid pits. Occipitomastoid suture visible on R,
running just medial to, and in parallel with, anterior
half of medial edge of mastoid notch. More posteriorly,
notch and suture become more widely separated; suture
goes straight back, whereas notch runs more laterally.
Throughout, plane of bone along occipitomastoid su-
ture is more or less smooth; posteriorly and medial to
suture, bone is excavated (thus, there is no recognizable
occipitomastoid crest despite raised appearance of
suture posteriorly). This shallow excavation is bounded
medially by a short, low Waldeyer’s crest, medial to
which is another smd, shallow depression.
Parietomastoid suture moderately long, and gently
upwardly sloping. Bilaterally is a long a/p, moderately
tall s/i, almost rectangular, asterionic ossicle. Above each
ossicle, lambdoid suture is at first only gently sloping,
but medially it rises more sharply (thus there is a modest
anterior lambdoid suture). Lambdoid suture itself arcs
moderately across lambda. Occipital plane more or less
featureless, except for a rounded angle in its midsection
above superior nuchal line. Occipital plane wide but
only moderately tall. Superior nuchal lines become more
prominent as they arc upward and medidy, and then
recurve downward to converge at midline. Below them
lie large, slightly scarred depressions for muscle attach-
ment. Above this area of convergence the bone is
smooth, and appears elevated relative to the depressions
below. No distinct external occipital protuberance.
Occipital crest emerges low down on nuchal plane, just
behind foramen magnum. On either side of crest lies
a small, moderately excavated depression.
Lambdoid, part of sagittal, and tiny bit of coronal
suture visible. Lambdoid suture deeply denticulated,
and sagittal moderately so; coronal only finely dentic-
ulated. Lambdoid suture unsegmented; only S1 of
sagittal suture can be distinguished.
Preserved internally is part of what would have been
a very long, markedly elevated frontal crest. Superior
sagittal sinus visible only posteriorly. Internal occipital
protuberance low and moderately broad, lying midway
down on nuchal plane. R transverse sinus takes origin
well above internal occipital protuberance, and loses
some definition as it courses laterally, becoming more
pronounced again as it runs into large sigmoid sinus. L
transverse sinus faint; emerges level with protuberance,
and quickly fades out. Sigmoid sinus quite excavated.
Impression for R occipital pole broader and shallower
than deeper L. Reverse applies to impressions for cere-
bellar lobes, which face slightly posteriorly. On both
sides, posterior part of petrosal is preserved; each has a
very faint rise in region of arcuate eminence; superior
petrous sinuses on both sides very broad and deeply ex-
cavated. Region of subarcuate fossa closed off on both
sides. As seen on L, frontal poles did not extend com-
pletely over orbital cones.Omo I
Rear of broken, repaired cranial vault, plus fragment
of mid-portion of frontal bone, including part of
glabella and medial supraorbital regions. Also part of
L lateral supraorbital region, an unidentifiable piece
of cranial vault bearing a depressed fracture, and frag-
ments of L and smaller R orbital regions, including
the zygomaticofrontal suture on both sides. On the L
is a zygoma lacking temporal process that matches the
piece above. Also a piece of R premaxilla and anterior
maxilla, with partial alveolus for I1 and roots of 12-P1
and a crushed, reconstructed L ramus with only the
lateral surface of the bone preserved, and lacking
coronoid. Fragmentary and reconstructed partial L
mandibular corpus, across symphysis from LM1 to
RP1, as indicated by broken roots. Missing most of
alveolar region.
Cranial vault moderately thick boned. Back of
skull tall and steeply rounded in profile; coronal suture
lies far back, taking bregma with it, suggesting a
steeper rather than more sloping frontal. Orienting
frontal crest on frontal fragment vertically indicates
frontal rose steeply and fairly directly from swollen
glabellar region; was probably quite domed in profile.
Smooth profile around back of vault carries well down
tall occipital plane to region of superior nuchal line,
where this curvature angles forward and down. Also,
occipital plane undercut by horizontal transverse sulcus
on nuchal plane in front of superior nuchal line. From
behind this is a tall, semi-“roofed” cranium. With tem-
porals missing, impossible to determine point of maxi-
mum width, although it probably lay above mastoid
processes. Sides of vault were probably quite vertical,
curving in quite high up toward slight midline rise.