In the temporal bone

Temporal bone

The temporal bones are situated at the sides and base of the skull, and lateral to the temporal lobes of the cerebrum.The temporal bone supports that part of the face known as the temple.-Parts:The temporal bone consists of four parts:* Squama temporalis...

, above and between the aquæductus vestibuli is an irregular depression which lodges a process of the dura mater

Dura mater

The dura mater , or dura, is the outermost of the three layers of the meninges surrounding the brain and spinal cord. It is derived from Mesoderm. The other two meningeal layers are the pia mater and the arachnoid mater. The dura surrounds the brain and the spinal cord and is responsible for...

 and transmits a small vein

Vein

In the circulatory system, veins are blood vessels that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood to the heart...

 and the subarcuate artery a branch of the internal auditory artery, which is an end artery that supplies blood to the inner ear ; in the infant this depression is represented by a large fossa, the subarcuate fossa, which extends backward as a blind tunnel under the superior semicircular canal

Superior semicircular canal

The superior semicircular canal is a part of the vestibular system and detects rotation of the head around a rostral-caudal axis.-Structure:...

.

It is extensive in most primates (except for great apes) and nearly all mammals. In these animals, the subarcuate fossa houses a part of the cerebellum, the petrosal lobe.