THE KEILOR FOSSIL SKULL: ANATOMICAL DESCRIPTION 63 
lower surface. The knife edges, when adjusted to support a skull, 
are in the same horizontal plane. Attachment C’ is not adjustable 
vertically, while D’ is adjustable both vertically and horizontally 
and it can be clamped in either direction by thumb-screws. 
An adjustable part, E, attached to the front of the frame pro- 
vides support under the maxillae; this part resembles a tuning 
fork with the handle attached to the kubus, and the two arms bent 
so as to give support under the maxillae. The two arms are 
separated about 20 mm. so as not to interfere with measuring, or 
drawing in the median sagittal plane. 
FIG. 1. 
The two poria points can rest on the ends of the knife edges, or 
the ends can be inserted as far as necessary into the meati. In 
either case, the knife edge, resting against the inferior border of 
each orbit, must be adjusted vertically to correspond horizontally 
with the poria. If the inferior border of one orbit or one prorion 
is missing, a skull can still be orientated reasonably accurately. 
Fragile skulls can be given additional support in the kubus by 
means of thread, wire, or plasticine. 
By turning the kubus so that different aspects rest on the bench, 
the skull can be orientated in the Frankfurt plane or in any plane 
at right angles to it. 
