or plane). Area across glabella broken; appears that
supraorbital tori were more or less continuous across
it. Temporal lines emerge just behind lateralmost part
of superior orbital rims and run straight backward.
Judging from broken supraorbital margins, it appears
that frontal sinuses did not extend as far as midpoint
of orbits or very far up into frontal. Viewed from
above, supraorbital profile retreats from glabella, then
curves slightly forward again as it proceeds laterally.
Also, supraorbital region broad and post-orbital
constriction minimal. From what remains of L side of
frontal, appears that frontal lobe extended well above
orbit.
Skull Rear: Profile curves smoothly to a point well
below lambda, where a shallow horizontal depression
forms the upper boundary of a noticeable bulge at
the broad, ill-defined junction between the occipital
and nuchal planes. Nuchal plane slopes forward at a
moderate angle (ca. 45 degrees) to the very posteriorly
placed foramen magnum. In posterior view, cranium
(as reconstructed) is rather straight sided, curving only
superiorly. Auditory meatus on both sides moderate in
size, slightly compressed a/p, tilted forward. On both
sides, vaginal process well separated from mastoid
process and forms posterior boundary of what appears
bilaterally to be an a/p long, m/l narrow, moderately
deep articular fossa. Again on both sides, styloid
process thin, incorporated into peak of low, thin
vaginal process that fades out before reaching lateral
edge of very short ectotympanic tube. Stylomastoid
foramen lies close to base of styloid process on L, but
far lateral to it on R. As seen on R, parietomastoid
suture horizontal and moderately long; it terminates in
what appears to be a parietal notch lying above and
posterior to midline of the relatively thin, forwardly
angled, probably quite pointed mastoid process.
Probably (but this is difficult to demonstrate defin-
itively), the mastoid processes did not project much
below the plane of the posterior cranial base. At most,
there is a slight swelling above the anterior part of
mastoid process that flows obliquely down and
forward to midway across the top of the auditory
meatus. At this point, it would probably have
expanded laterally to form the posterior root of the
zygomatic arch. Impossible to ascertain the presence of
a mastoid notch medial to mastoid process; on R is
curious ovoid and moderately deep depression on the
posterolateral aspect of the process. Occipitomastoid
sutures and regions medial to them are missing. As
reconstructed, foramen magnum lies at an angle to the
broad, flat, apparently very alp short basiocciput.
Within the basiocciput is a large sinus (probably a
posterior extension of sphenoid sinus). Lambdoid
suture undifferentiated; rises steeply from asterion
(since lambda is missing, it is impossible to ascertain
whether the lambdoid sutures peaked there). Internal
structure too weathered to describe, except to note the
absence of a subarcuate fossa on petrosal, and probable
absence of a superior petrous sinus.Maxilla. Floor of nasal cavity and the putative
areas of maxillary sinuses obscured by clay. As they
exist, tooth rows curve inward strongly at rear. It is
much more likely that they originally formed a short,
broad parabola. With this alteration, infraorbital
planes face more completely forward (rather than
receding sharply as in the reconstruction). Infraorbital
planes also appear to have curved forward beside nasal
aperture (implies quite forwardly jutting malar
regions). Canine fossa not identifiable. Anterior root of
zygomatic arch took origin close to alveolar margin;
judging from L, it probably curved strongly laterally.
Palate deep, and all surrounding surfaces slope steeply
toward its center. Trace of an incisive foramen that
would have lain far forward, above I1 crowns. Teeth
highly eroded, having lost virtually all morphology
(even, in some cases, indications of their original size).
11s were apparently not very broadly spatulate. C
crowns were not very robust. Ps and Ms were small.
M3 must have had a swelled-out hypocone.REFERENCES
Brauer, G. et al. 1992. A first report on the ER-3884 cra-
nial remains from Ileret/East Turkana, Kenya. In: G.
Brauer and F. Smith (eds), Continuity or Replacement?
Rotterdam, A. A. Balkema, pp. 111-119.
Brauer, G. et al. 1997. Modern human origins backdated.
Nature 386: 337-338.
Feibel, C. et al. 1989. Stratigraphic context of fossils from
the Omo Group deposits, northern Turkana Basin,
Kenya and Ethiopia. Am. J. Pbys. Anthropol. 78:
595-622.Repository
National Museums of Kenya, PO Box 40658, Nairobi,
Kenya.