I) is a single knob, being formed almost wholly by the basi-occipital, while the lateral occipitals (often perversely called exoccipitals) take but little share in it.
Parker.) bo, Basi-occipital.
Later on fused with, a pair of membrane bones, the basi-temporals, homologous in part with the parasphenoid of lower vertebrates.
Rbs, Rostrum of basi-sphenoid.
The circular space on each side of the basi-temporal (bt.) is the opening of the anterior tympanic recess.
The basi-pterygoids (bpg) are mere knobs, and the common eustachian opening is seen between them.
B.br, Basi-branchial, or urohyal, answering to the rest of the basibranchial series.
Genera: (a) Ore supero; basi se affigens: Actinia, Ascidia.
The cleido-mastoid generally arises from the basi-occipital, and the pectoralis major is connected with the latissimus dorsi.