252 Epwın CHaAPın STARks, 
pterotic, the prootic, and the exoccipital, continued between the two 
latter bones entirely separating them, thence between the anterior 
end of the basisphenoid and the prootic. The prooties are entirely 
separated from each other by cartilage at the median line, where 
they are covered by the parasphenoid. A very large cartilaginous 
area is present on top of the cranium between the epiotic, the 
parietal, the frontal, and the pterotic. The supraoccipital is entirely 
separated from the exoceipitals. Some of these bones come in contact 
when the skull is dried and the cartilage shrunk. 
The interorbital membrane is double and the two sides widely 
separated from each other. The base of the cranium is simple, or 
without a myodome. 
The oceipital condyle is simple, componed of the basioccipital 
only, and similar to the centrum of a vertebra. The pit in its face 
is much deeper than usnal. 
As viewed from below only a lateral wing on each side and 
the posterior end of the basioccipital appears from beneath the wide 
parasphenoid. 
The exoceipitals do not meet either above or below the foramen 
magnum. They are pierced by the usual vagus foramen on their 
lower posterior surface. Posteriorly in place of the usual ee 
for articulation with the atlas is a small sharp spur. 
The supraoccipital is very small and does not extend between 
the posterior ends of the frontals. There is only an indication of 
a crest on its oblique posterior surface. 
The parietals lie parallel with each other and are well separated 
by the supraoceipital. Anteriorly they extend past the posteriot 
ends of the frontals, while posteriorly they overlie the anterior upper 
surface of the epiotic. 
The epioties are shaped like a hollow cone with its opposite 
sides crushed nearly together. To the apex of each the ligament 
from the upper limb of the posttemporal is attached. 
The pterotice does not send a lateral process backward, but has 
a moderate lateral angle opposite its middle. 
The prootic is not pierced for the passage of the fifth and 
seventh nerves, but has a deep notch in its anterior edge. Just 
above the notch a long neural tunnel extends longitudinally 
backward for nearly the whole length of the bone, opening 
widely posteriorly. Im the interior of the cranium a sharp 
