An element tentatively identified as the
prootic has a concave surface in occipital view (Fig.
handleyi, a large surface of the petrosal bone (including the sulcus of the
prootic sinus) is exposed through the anteroposteriorly elongated subsquamosal foramen.
Anterior portion of parasphenoid cartilaginous, covering vomer; posterior portion of parasphenoid in contact with
prootic and basioccipital.
Peculiar, large 'auditory foramen', which is usually an ovoid opening on the ventral face of the
prootic through which the utricular otolith is visible.
Ventromedian projection from
prootics extending between bilateral rami of basisphenoid.
Prootics and exoccipitals fused; entire posterior end of skull well ossified; optic foramina ventrally marginated by cartilage; oculomotor foramina marginated anteroventraly by cartilage;
prootic and jugular foramina with bony margins; with small bony knob formed below epiotic eminences above occipital condyles.
The paired
prootics are large and broken, attached posteroventrally to the incomplete enlarged basiocceptals.
It bears a pair of ascending flanges, which suture with the pterosphenoids and
prootics.
Smelt vertebrae cannot be used to enumerate individuals, whereas several herring bones commonly recovered in scats are unique or are structures with definite sides (
prootics, atlas and axis vertebrae), and even highly eroded herring bone retain characteristics identifiable to species.
It bears a pair of salient ascending flanges, which suture with the pterosphenoids and
prootics.