142 A F R I c: h
anteriorly with mastoid gutter. Medial to this putative
stylomastoid foramen, and associated with vaginal
process, is smaller, more circular pit (possibly styloid
pit). Suprameatal regions, as well as lateral parts of
articular fossae on both sides, broken off. What is left
of the articular fossae is deep, with rather shallowly
sloping anterior and posterior sides. Articular enii-
nence is prominent and smoothly curving; it expands
somewhat anteriorly at its medial end to form a rela-
tively modest medial articular tubercle. No evidence
of a postglenoid plate at back of fossa.
Petrosals badly eroded. As seen on the R, carotid
foramen was evidently large and downwardly facing. In-
ternally, R petrosal surface bears a distinct, moderate-
size, relatively low mound; on the L is a much more
prominent dome-like eminence. On both sides, petrosal
region is quite narrow. On the L, a no subarcuate fossa;
morphology on both sides is damaged inferior to this, so
it is impossible to determine whether an inferior fossa
was present. Both foramina ovales preserved; they lie
entirely in sphenoid and lateral to the lateral pterygoid
plates.
Maxilla Isolated, badly damaged. Medial orbital
walls converge drastically posteriorly, with a very deep,
sunken region of cribriform plate between them.
Inferomedial portions of orbits are preserved
bilaterally; the anterior lacrimal crests appear to lie
more on face than in orbit and the posterior lacrimal
crests lie just within the orbital margin, projecting so
that the long, shallow, teardrop-shaped lacrimal fossa
faces somewhat forward. Interorbital region is badly
crushed but region of nasonasal suture is slightly ri-
dged. Nasal bones were vary narrow and probably
tapered slightly superiorly. Length of nasal bones is
impossible to determine; preserved superior portions
show a very slight anterior curvature. Lateral margin of
nasal aperture (on R) is largely undeformed; was very
rounded, with low facial pillar lateral to it. Pillar runs
down to region of C. Floor of nasal cavity flat; runs
smoothly and without obstruction into relatively short,
anteroinferiorly curving nasoalveolar clivus. Contour
of nasal aperture was probably simply piriform.
Anterior root of zy-gomatic arch took origin some
distance above the alveolar margin. Body of zygoma
faced forward. Palate was broad, long, and quite flat.
All preserved teeth extensively worn and badly
eroded. FU1 crown partially preserved; appears not to
have been very large, but was much larger than 12. I2
very tiny and nonspatulate. Preserved R and LCcrowns appear to have been thinly conical. On the L,
Ps appear to have been simple, bearing only paracone
and metacone. P2 was slightly shorter m/d than P1.
M1 is smaller than either M2 or M3 on the R, but
slightly larger than either on the L. Increasingly
emphasized from M1-3 is distal enlargement of
hypocone. Little other dental morphology is left.MANDIBLE
Corpus lacks rami; damaged at front, with only crowns
of RM2 and 3 preserved. Dental arcade formed in a
narrow parabola, although internal contour of mandible
more V shaped. Corpus extremely shallow; thins
rapidly beneath tooth-bearing bone. Part of symphyseal
surface preserved; externally slopes back quite steeply,
with no ornamentation visible. Internally, postincisal
plane curves back and then down and around toward
fair-sized genial pit. Virtually no submandibular fossa
where surface is preserved on the L. M3 would not
have been hidden by ramus, as shown by anterior root
of ramus on both sides. M2 and 3 heavily worn and
eroded; they are elongate m/d and somewhat rounded
posteriorly. Ml was apparently smaller than either,
judging from preserved roots. C alveoli quite large, for-
wardly placed, squeezing the four I roots between
them. Both Pls had two distinctly splayed roots and
wide b/l, compressed m/d, and obliquely oriented in
jaw. Part of LM1 crown preserved but uninformative.KNM-ER 1590. Many small cranial vault pieces,
reassembled into larger pieces, notably parietals
including coronal and sagittal sutures. Also several
isolated teeth, not all from same individual.
Cranial bone relatively thin; braincase probably rel-
atively large. As reconstructed, parietals arc smoothly
but not steeply across in coronal section. No evidence
of any temporal lines. No cresting along sagittal suture.ER 1590C. RC1 (identified in catalog as L). Surface
weathered; mesial and distal slopes curve smoothly
descending from crown apex. Mesial edge bears
secondary peak just below apex of b/l wide crown.
Lingual pillar medially displaced and compressed.
Mesial to pillar is narrow, deep fovea; posterior to it is a
large shallow fovea.ER 1590D. LC1 (identified as R). In general shape
and outline, and with a secondary peak, this tooth is
similar to ER 1590C. Lingually, however, ER 1590D
bears two compressed pillars with a shallow concavity
between them, and deep foveae in front and behind.