P. gradilifrons reached up to in length. The
cerebral hemispheres are the widest portions of the
endocast of
Paralligator; they are approximately 2.5 times wider than the olfactory tract and about 1.5 times wider than the
midbrain and the portion corresponding to the
medulla oblongata. The olfactory complex is as long as the remainder of the endocast and is thus highly anteroposteriorly elongated. The
olfactory tract of
Paralligator is transversally narrow and highly elongated, and it expands posteriorly into the cerebral hemispheres and anteriorly into the
olfactory bulbs, which are paired and are divided by the mesethmoid facet, diverging anteriorly at an
angle of approximately 25°–30°. Posterior to the cerebral hemispheres lies the mesencephalic portion of the endocast, which is notably constricted when observed from a dorsal view. Posterior to the mesencephalic portion of the endocast lies the anterior portion of the
rhombencephalon, consisting of the
pons and
cerebellum; this section is notably laterally and dorsoventrally expanded. The
flocculus is not developed. The medulla oblongata is wider lateromedially than it is deep. == Taxonomy ==