The spinal cord is protected by the vertebral Column.

http://en.wikipedia.org/wiki/Anatomy

The spinal cord is protected by the vertebral column and is above the notochord and the gastrointestinal tract is below it.Nervous tissue is derived from the ectoderm, connective tissues are derived from mesoderm, and gut is derived from the endoderm. At the posterior end is a tail which continues the spinal cord and vertebrae but not the gut.