Transverse section through a spinal cord segment and meninges (Luxol Blue stain). The central canal (asterisk) is surrounded by butterfly-shaped gray matter. The blue stained white matter is superficial to the gray matter. Pia mater is attached along the white matter surface. Dura mater (D) is the most superficial menix. (An epidural space separates dura mater from periosteum lining the vertebral canal.) Arachnoid lines the dura mater. Bilaterally, a denticulate ligament extends from pia mater to dura mater. The ligament suspends the spinal cord so that it is completely surrounded by subarchnoid space and cerebrospinal fluid.