Cope. ] 72 [Feb. 17, 
separated by a groove at its apex. The posttympanic is a flat fan- 
shaped bone appressed close to the postglenoid process. Its inferior 
edge forms a ridge running horizontally inwards and posteriorly, and 
enclosing a triangular space with the postglenoid, which is pierced by 
the postglenoid foramen. Between the foramen and the bulla of the 
ear is a small pisiform tuberosity. The otic bulla is small, and its long 
axis is longitudinal; its width is a little greater than the space between it 
and its fellow, and equals the space between the apex of the postglenoid 
process and the nearest point of the paroccipital. The basioccipital is 
weakly keeled at the middle line behind, but it is grooved at the anterior 
edge through the presence of a tuberosity on each side of the middle line. 
The groove soon disappears on the sphenoid. The inferior ala of the sphen- 
oid forms with the pyramidal process of the palatine a long wall, which ex- 
tends from the posterior contact with the maxillary bone tothe internal base 
of the glenoid cavity. Its inferior margin is double, or grooved, the exte- 
rior edge being deeper posteriorly, the interior the deeper anteriorly. The 
posterior nareal border is divided by an osseous septum of 15 mm. in 
length on the inferior edge ; the anterior border of the nares attains the 
line of the posterior edge of the last superior molars. The palate is flat, 
except a slight recurvature at the bases of the molars. 
The sutural boundaries of the nasal bones are about the same as in the 
B. subequans. Their anterior extremities are fortunately preserved. They 
are deeply notched, so as to be bifurcate, the internal angle being about 
as long as the external. The facial part of the lachrymal is subquadrate 
and its anterior suture forms a nearly straight line with that of the malar 
bone. The superior squamosal suture reaches half way to the sagittal 
crest, but not to the lateral occipital. The maxillopalatine extends ante- 
riorly to a point opposite the middle of the first true molar. The premax- 
illary extends to within 50 mm. of the frontal, while the latter touches the 
maxillary by a suture of 10 mm. in length. 
The foramen magnum is small. The lachrymal is single. The infra- 
orbitale issues above the middle of the p. m. ii. The supraorbitals are close 
together, being separated by a space equal to one-eighth the interorbital 
width. The /. opticum is rather large and is quite distinct from the 
J. rotundum, though near it. The latter and the f. sphenodrbitale appear 
to be united into a single large orifice. The f. ovale and f. lacerum anterius 
are not distinct. There is no f. lacerum medius, and the f. lacerum pos- 
terius is very narrow. The f. stylohyoideum is rather large; the f. post- 
glenoideum looks downwards and inwards from between the posttympanic 
and postglenoid plates. The f. condyloideum is well isolated ; it is oval 
and looks downwards. The f. magnum is a wide transverse oval. The 
meatus auditorius externus looks upwards into a triangular groove-like 
fossa of the triangular posterior face of the zygoma. There is one large 
postparictal foramen. No supraglenoid foramen. Mastoid foramen small, 
below the edge of the posttemporal crest. Palatine foramina opposite the 
middle of the first true molar. 
