280 SHOUFELDT. [Vor2ik 
of a pyramid, the lateral and upper sides of each being also 
formed by the supraoccipital. The lateral aspect of this pyra- 
mid is overlapped by the epiotic (£/.0.), while outwardly its 
free margin articulates with the squamosal (Fig. 3). 
Regarding one of these epzotics, we find that its fan-like 
portion is finished off behind by a semicircular piece, which is 
thickened below, where it becomes firmly attached to the neigh- 
boring bones. The blade portion is longitudinally fluted, but 
no rugosities are found upon it. This does not apply to the 
element at its outer side, the sgwamosal (Sq), which element 
develops very conspicuous rugosities upon its upper aspect in 
direct continuation with the longitudinal ones on the long, back- 
ward-extending process of the corresponding frontal (Fig. 3). 
At the distal extremity of the squamosal I detect a small, 
flake-like piece of bone, thoroughly attached, though individu- 
alized by sutural traces, which I take to be the representatives 
of the pterotic (Pt.O.). Beneath and beyond, the squamosal 
seems to make the usual ichthyic articulations with the post- 
frontal (Pzf) and the prootic (P7v.O.). At its under side we 
find a small hyomandibular facet (Fig. 4, “/). 
A postfrontal of considerable size (P¢/) develops at its outer 
side, a sharp, descending, spicula-form process of bone, which is 
transversely pierced at its base by a small foramen. The infe- 
rior articular sutural trace of the postfrontal, as I make it out, 
is subcircular in outline, and closely meets corresponding mar- 
ginal concavities offered by the prodtic and alisphenoid. 
Each alisphenoid is necessarily a very extensive ossification, 
forming, as they conjointly do, the major part of the bony wall 
of the posterior aspect of the immense orbit (As). 
In front they articulate with far smaller ovbztosphenotds, which 
in their turn meet in the median line anteriorly (Os). Now 
above the basisphenoid (4s), the alisphenoids and orbitosphe- 
noids are separated from each other, mesially, by a vertical 
vacuity, broadest below, graduaily tapering to a blunt apex 
above, which constitutes a great fenestra for the anterior wall 
of the cranial casket (Fig. 4). 
As already stated, the hinder portion of the ethmozd (Eth) 
forms the mid-roof of the orbital space. This division of the 
bone is of an oblong outline, being encroached upon by the 
common, circular, anterior margin of the obitosphenoids behind, 
