Hip bone The hip bone first appears in fishes, where it consists of a simple, usually triangular bone, to which the pelvic fin articulates. The hip bones on each side usually connect with each other at the forward end, and are even solidly fused in lungfishes and sharks, but they never attach to the vertebral column. In the early tetrapods, this early hip bone evolved to become the ischium and pubis, while the ilium formed as a new structure, initially somewhat rod-like in form, but soon adding a larger bony blade. The acetabulum is already present at the point where the three
Squamous part of the frontal bone small aperture in the upper part of the notch transmits a vein from the diploë to join the supraorbital vein. The supraorbital margin ends laterally in the zygomatic process, which is strong and prominent, and articulates with the zygomatic bone. Running upward and backward from this process is a well-marked line, the temporal line, which divides into the upper and lower temporal lines, continuous, in the articulated skull, with the corresponding lines on the parietal bone. The area below and behind the temporal line forms the anterior part of the temporal fossa, and gives origin to the temporalis muscle. Between