Spinal cord ( SP ; Galen, c162-c176 ) : The caudal (Cleland, 1879) topographic division of the cerebrospinal axis (Meckel, 1817); the rostral (Schulze, 1893) topographic division is the vertebrate brain (Cuvier, 1800). The usual criterion for distinguishing the two divisions in the adult is that the vertebrate brain lies within the skull whereas the spinal cord lies within the spinal (vertebral) column, although this is a difficult problem in practice; see Crosby et al. (1962, pp. 112-120). Definite knowledge of the spinal cord dates to Hippocrates in Fleshes (see translation by Potter, 1995, p. 139), and Galen (c162-c176) used the term specifically-see translation by De Lacy (1978, p. 85). Common synonyms include medulla spinalis (Hippocrates), or spinal medulla in English, and spinal marrow (Bannister, 1578).