However, the autonomic ganglia of the Vagus nerve (X) form lie outside of the head, frequently within the organ which they innervate. In the case of the gut, for example, the autonomic neurones do not form distinct ganglia, but rather the preganglionic neurons synapse within the Enteric nervous system.
^Purves, Dale, George J. Augustine, David Fitzpatrick, William C. Hall, Anthony-Samuel LaMantia, James O. McNamara, and Leonard E. White (2008). Neuroscience. 4th ed. Sinauer Associates. pp. 12–13. ISBN978-0-87893-697-7.CS1 maint: Uses authors parameter (link)