THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -The deepest layer of the meninges, the pia mater, is composed of two layers and, unlike the arachnoid, follows the contours of the sulci and gyri. The outer layer of the pia, referred to as the epipial layer, contains collagen fibers; the inner layer, or the intima pia, contains elastic and reticular fibers.

Detailed explanation-2: -Pia mater: This is the inner layer, closest to your brain tissue.

Detailed explanation-3: -The periosteal or endosteal layer of the dura mater is simply a layer of periosteum that covers the inner surface of the skull. The layer does not extend beyond the foramen magnum to become contiguous with the dura mater of the spinal cord. The spinal cord dura mater has no periosteal layer.