The functional significance of the nucleus dorsalis, its relationship to incoming fibers and the course and termination of the fibers arising from its cells have been the subject of controversial discussions since Clarke's1a description of the nucleus in 1851.
It was early demonstrated that the nerve endings ramifying about the cells of Clarke's column come from fibers of the dorsal nerve roots which swing into the posterior column. These fibers were interpreted by Gaskell2 as being visceral rami. He showed that the visceral rami were limited to three regions of the central nervous system: (1) a cervicocranial region, (2) a thoracic region and (3) a sacral region. Then he pointed out that Clarke's column forms a discontinuous column, the cell groups of which correspond accurately to those regions. He said: "The connection of these fibers with this column of cells is to my mind proved conclusively by the